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PH'SICA' ''O'RAPH' OF WORC'ST'R.
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STA'DI'' at the summit of Vernon Street hi l l and lookingwestward and northwestward , we overlook the deep va l iey
bordered on one side by Millbury Street and on the otherby Southbridge Street , and see beyond the higher land ,
a long the crest of which is Main Street from May Streetto New Worcester hil l ; and , sti ll more distant , rising fromthis , a rol l ing , bil lowy area looking as if the surface of theearth had been ra ised into great dqme- l i ke waves , and theretr ansfixed ; and fina l ly we see , in the distant backgroundthe highlands of Leicester and Paxton , a long the summitof which we trace the horizon with its upward curve showing us the outline of Asnebumskit . O r , again , if we standon an open spot on Belmont Street hi l l and look westward ,we overlook the val ley beneath followed by the BostonMaine and Fitchburg Railroads , and see beyond the samebi l lowy landscape with the Paxton and Leicester highlandsfor their background . As we look at thi s beautiful andvaried landscape , confusing though it may seem , we mayj ustly ask what these highlands , these val leys , these dome'ike hil l s , these plains , these meadows , these streams , theseponds and lakes mean . What is the story they tel l a s ?
For in nature there i s no chaos , everything has its meaning ,i f only we have eyes to see , and the perception to understand the revelationIn studying the physical geography of Worcester , let asbegin near the northeast corner . Stand ing at the crossing
1 The reader shou ld have before h im while read ing this the W orcester and
W ebster sheets of the topographic map of Massachusetts. These may be oh
tained from the U . S. 'eological Survey or fr om the Comm issioners of the
Topogr aphic Map of Massachusetts, 1 1 Mt . V ernon St ., Boston , Mass., at fivecentsa sheet.
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of the Boston Maine Rai lroad , near the Summit station ,we are nearly 640 feet above the sea- level . We then passto the south
, fo llowing Burncoat Street , ascending a hil l at
fi rst somewhat steep and then more gentle in its ri se , unti lwe are more than 700 feet above the sea . Looking to theleft where the v iew is unobstructed , or going to the easternedge of the hi l l , we may trace the course of Poor FarmBrook
, w inding its way down a qu ite steep slope of 60 feetto the mile
,until its waters become a part of Lake Quin
sigamond . O h the right , though general ly hidden , i s theupper course of Mi l l Brook . Rising in the southern partof Holden
,at an altitude of 800 feet above the sea, i t flows
for about a mi le to the southeast , then fol lows the BostonMaine Rai lroad , i s increased by the waters of North Pond ,and forms the succession of ponds of which Sal isbury is thelast . The rains fal l ing on the eastern slope of this hi l l thatwe are traversing final ly flow i nto Lake Quinsigamond ,and those fal l ing on the western slope go to swel l the watersof Mil l Brook . We are on the divide between these twowater—coursos. Continuing south along Burncoat Street toAdams Square , we descend about 1 20 feet ; we then fol lowLincoln Street to the east for about half a mile and turni nto the fields ; again ascending we mount to the top of thehi l l on the eastern sl ope of which is the State Lunati c Hospital . We are now 760 feet above the sea . Standing onthe open ground , we look around . The eye , following thehorizon , sees almost the perfect circumference of a circle ,except where a few heights l ike Asnebumski t and Wachusett produce a convexity in the l ine . And if we descendon any side of the h il l , though the horizon constantlychanges its p osition , i t i s sti ll thi s regular l ine . There isonly one surface that wi l l always give the circumference ofa circl e for the horizon , and that i s a pla in . In otherwords , in spite of the various inequal ities i n the earth’ssu rface noticed as we walk or ride from Worcester to theneighboring towns , the land of Central Massachusetts i s an
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approximate plai n , or peneplain as Prof. Wil l iam M . Daviscal ls it .
But no sooner do we reach the summit of Millstone Hi llthan we begin to descend the southern slope to BelmontStreet . Here is Bel l Pond , formerly cal led Bladder Pond ,one of the three natural ponds of Worcester . We continne directly south from Bel l Pond , the mpe at timesbeing almost precipitous , and descend in al l 280 feet intothe narrow gorge , through which Shrewsbury Street andthe Boston Albany Rai lroad enter the city . As you havemany times passed through this on your way to and fromthe beautiful lake beyond , have you ever asked yourself the
questiom— ' Why is there this sudden break between
Mil lstone Hil l and the h ighland south of the BostonAlbany Railroad ? ” Thus the very landscape about us i steeming with questions . O n crossing the rai lroad , continning to the south , we immediately ascend a steep slope ,and at the highest points on ‘ this hil l find ourse lves 700 feetabove the sea , about 60 feet below the highest part of Mil lstone Hil l . Over the crest of thi s hil l passes PlantationStreet , which we fol low , and thence cross to ProvidenceStreet hil l about 1 00 feet lower . But here the elevatedland , which north of the Boston Albany Railroad is aridge about hal f a mi le wide at the top and two miles wideat its base , becomes broad and triangular , gradual'y s lopingon the east to Lake Quinsigamond and QuinsigamondRiver , and on the west and southwest sloping quite abruptlyto the val ley of Mi ll Brook and the Blackstone . Thisbroad area has many rounded hi l ls and is a rol l ing uplanddrained by many brooks , the longer and larger of whichflow to the east and southeast because of the longer slopes .But the most. noticeable fact about this region is thesteep slope on the west , there be ing a fal l of ful ly 1 60 feetfrom the crest of Vernon Street to the level of the Blackstone at Quinsigamond Vi llage . But again the land riseson the other side of the river 260 feet to the summit of
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Pakachoag Hil l.There seems to have been left here i n
this high land,a gateway through which the Blackstone
might pass to the south . But continuing to the south , wefol low the crest of Pakachoag Hill , 700 feet above the sealevel
,across ' the Worcester l ine into Auburn. Nor does
this high land end here . It i s continued in the high landeast of the Norwich Worcester Rai l road and Lake Chau
bunagungamaug through Auburn , Oxford and Webster .
This high land extends east to the Blackstone Val ley andconstitutes a broad plateau .
We have thus , in detai l , outl ined a marked ridge of landcrossing Worcester from north to south approximately , anda noticeable characteristic in it is that frequently we find theledges appearing through the loose material that general lycovers them . At the Summit , the deep cut of the BostonMaine Rai lroad exposes the l edge ; along Burncoat
Street , especial ly as we approach Adams Square , ledgesfrequ ently appear ; Mil lstone Hil l shows the underlyingledge everywhere ; the h il ls over which Plantation , Providence and V ernon Streets pa ss have frequently but a thincoating of earth , which is ineffectual in conceal ing the firmledges beneath ; and so fina l ly with Pakachoag Hi ll , theledge outcrops di rectly back of Holy Cross College
,at the
summit of the hi l l , and to the south large areas of ledgeare entirely destitute of covering . But it wi l l not benecessary to fol low this farther to the south satfice i t: tosay , that this r idge and the plateau into wh ich it broaden sto the south , are throughout composed of ledge with a thincoating of loose materia l spread over the rock—sur t
’
aee .
In other words , outcrops of ledge show as that this ridgetraversing the eastern part of Worcester
,rising 200 feet
and more above the valley of Mi l l Brook and 300 feet andmore above Lake Quinsigamond , i s a ridge of rock havingbut a thin covering of loose earth over the rock .
In l ike manner we may trace rocky highlands along thewestern border of Worcester . Starting with Asnebumskit ,
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ri sing 14 00 feet above the sea , we may follow a border ofh igh land elevated 1 000 feet above the sea , ledges appearing every now and then , to the south , through Cherry Valley , on to 'rowl and Prospect Hi l ls in Auburn and RockyHi ll in Oxford and other hil ls i n Webster and Dudley tothe Connecticut l i ne . But these hil l s do not constitute aridge . They are the eastern berder of the highlands ofPaxton , Leicester , Charl ton and Dudley ; and these highlands constitute a broad plateau , as did the highlands ofMil lbury , Sutton and Douglas to the east . The westernborder of the eastern plateau and the eastern border of thewestern plateau are approximately paralle l ; and throughAuburn , Oxford and Webster are a mi le or a l ittle moredistant from each other . Were it not for the val ley separating these two plateaus , — the val ley fol lowed by theNorwich Worcester Rai l road through Auburn , Oxford ,and Northern Webster , — these two plateaus would be continuous, and constitute one and the same plateau . The realre lation of these two plateaus wi l l be made clear before weare through with this study ; let a s now return in ourthoughts to Worcester .Between the Mi l l stone—Pakachoag rock-ridge on the east
and the high rocky land of the Paxton highlands on thewest , there are w i th in W orcester many elevations , somerival l ing in height the loftiest points of the eastern ridge .
Let us careful ly examine these b i l l s . They appear veryabundantly in the western part of Worcester . They eon
st itute the roll ing , bi l lowy surface seen as we look to thewest from Vernon Street h i l l . They are uniform in appea rance , havi ng the shape of a dome or of an elongated dome .O f these hil l s Newton Hil l is the type . These h il ls arefrequently grouped in clusters , as i n the region north and '
northeast of Peat Meadow , or i n rows , as in the regionnorthwest of Barber
’s Crossing . Their surfaces are smoothand regular as if laid out by the landscape gardener . Theyvary in height from 50 feet to more than 200 feet above
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the planes of the ir bases ; and the ir circular or el l ipt icalbases vary from one fourth of a mile to a mi le or a l ittl emore in diameter . These hil l s are not , however , l imitedto the western part of Worcester . The hil l s i n a row , ofwhich Mt . Ararat near North Worcester is the southernmost
,are such . They also occur on the top of the eastern
rock ridge . 'reen Hil l and the dome- l ike hi ll s cl usteredabout it belong with these . But as Newton Hil l i s thetype let us study i t in detai l . Its base i s nearly circular ;i t rises 1 60 feet above the surrounding lowlands ; it hasthe smooth , regular sides and the almost perfect domeshape . As we walked around its base while the workmenwere digging into its sides , at no po int did we see ledgeprojecting . As the trench was dug for the sewer throughPleasant Street , l edge was found only at a consi derabledepth . Also as we go up on the sides of the hi l l , weobserve many rock masses , — some lying in one position ,some in another, some of one kind of rock , some ofanother , — without any regularity or uniformity ; and al ittle careful observation convinces us that these are onlyrock fragments , not outcroppings of the sol id ledge . Intoone of these hi l ls east of Plantation Street the workmenhave out many feet for material out of which to makebrick , and they there show as exactly what we should findif we dissected Newton Hil l , — no ledge from top to bottom ,
nor from side to side . We are as sure of this as i f thedril l had penetrated from the foot of the fiag-stafi
’ to thebase , and from Highland Street to Pleasant Street . Whatwe say of Newton Hil l is true of these many dome- l ikeh i l ls of Worcester . But if they are not composed of ledge ,of what are they composed ? As these bi l l s are dissectedby various cuttings for streets , rai lroads , and the l ike ,there are found rock fragments of various k inds and ofa l l sizes from an inch or less in diameter to the greatmasses many feet through , which the untra ined eye mightmi stake for ledge . Those of the l ighter shades are gener
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ally of granite , often containing needles or crystal s of blacktourmal ine . These rock fragments are general ly roundedi n form and some are very l arge . 'ou wil l al so observesome of a reddish drab color . These wi l l be quite general ly angular in shape , not of large size , and wil l break intolayers when struck by the hammer . They have a veryfine , granular structure ; and the material of which theyare composed is ve ry hard . This rock is cal led quartzite ;and if we compare it with the rock exposed in the sewertrench of Pleasant Street at the very base of the hil l
,
ia fact the rock on which the h il l rests ,— we shal l see thatthe two are identical . A third variety , that you wi l l see ,wil l be of a drab to black color , of a scaly structure ,breaking into scaly masses presenting shining su rfaces , notgranular , but as if a large number of minute flakes hadbeen pressed together . This rock is cal led argi l l i te . 'extyou may notice a rock resembl ing the second quite closely
,
but coarser in gra i n , the l ittle scal es large enough to be seen ,the color varying from a redd i sh gray to a faded-brownishgray , presenting many gl i stening surfaces , breaking inthin slabs or sheets . from an inch to several inches thick .
This , because of the use sometimes made of such a rock . i scal led a Whetstone m ica schist . Besides these you mayfind rounded fragments of trap- rock , very rusty on theoutside , of some dark shade of gray within , and of a fineto coarse crystall ine structure . O r you may find massesof a l ight drab mica sch ist crowded with garnets .All of these and many more rock fragments wil l be found
imbedded i n a somewhat fine clay- l ike substance . This ,however , proves on closer examination to be ground rock ,not clay , which is decayed rock . With this ground rockis also much sand . Out of such a mixture have NewtonHil l and these other dome- l ike hi l l s been bui lt .But the kind of material in these hi l ls is not the only
fact to be noticed . This material i s not arranged in anyorder or regularity— the coarse and fine l ie together , they
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do not constitute layers as do the sands and clays depositedby currents of water . There may be the great roundedfragment of granite several feet in diameter and al l aroundit only the fine particles of powdered rock . Should we tryto dig into one of these bi l ls , or watch the workman as hedoes , we should qu ickly notice the remarkable hardness ofthe material . So hard is it that the steam- shovel is brokenagainst i t ; so tough is i t that the blast shoots from it asfrom the mou th of the cannon ; and so fi rm i s i t that thebuilder does not hesitate to rear the nine stories of marbleand granite upon i t as the foundation . But if we examinemany of these hil l s into which cuttings have been made weshal l observe in some of them a rudimentary cleavage thathas commenced to be developed . This is best observedwhere the bank exposed by a cu tting has been acted on byrain and wind ; the softer parts are worn away morerapidly , and so the fi rmer , more resisting parts projectbeyond the genera l surface .
These facts— the hardness , fi rmness , and incipient cleavage— in'dicate that this material has been subjected to greatpressure , which has welded together these loose particlesand masses of rock .
Another fact wil l not escape our notice i f we study thedissected dome—l ike hi l l on the east side of PlantationStreet . As we examine the masses of rock we shal lobserve that many of them are rounded
,but not so
smoothly and perfectly as are the pebbles in the brook bedor along the pebbly beach ; and we shall see that theserounded fragments are quite general ly scratched
,even
grooved , especial ly on what we shou ld ca ll the upper andlower surfaces ; and these scratches and grooves areparallel to each other and to the longest diameter of therock . This appearance i s j ust what would have been produced if the rock had been held in a somewhat yieldingmedium and then rubbed in one direction over rock surfaces . And there i s something that exactly matches this
.
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their longest diameters . The ledges beneath are a lsorounded
,pol ished
,scratched , and grooved as by some
agent moving over them from a direction 1 0— 1 5° east ofnorth
,and rubbing their surfaces with coarse and fine rock
material .With these facts in mind there are some things that wemay assert in regard to these b i l l s . They are not domesof decayed rock , as if the underlying ledge had been thehi l l and this rock had simply decayed and crumbled intothis loose material , as the ledges have decayed and crumbled in more southern latitudes . A large part of this rockmaterial must have been transported , because the rockfragments do not match the underlying ledges , and therefore could not possibly have come from them . But if we/compare these rock fragments with the ledges in Holdenand other towns to the north and northeast , we find theledges that they are l ike . These must then have beentransported by some agent from those ledges in Holden
,
W est Boylston , Sterl ing and other towns to the north andnortheast and deposited here in Worcester , thu s bui ldingup these hil l s .
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Such are the facts that stand out with special prominence as we attempt to read the story of these hii le, andthese must be explained if we hope to read the story‘ aright .O f the various agents that transport rock material— thecurrents of air , the currents of water upon the land and i nthe sea , the floating icebergs , and the great rivers of ice ,the glaciers draining the region of eternal snow and ice
1 O r if you w ish to have this transport ation of rock mater ial from thenor thdemonstrated w ith in a sma l ler area , go to the south of Mi l lstone Hi l l and notethe abundance of granite frag ments from that h i l l . Th is granite is unique,and none of the granite from other granite areas is to be mistaken for i t. Thestone wal ls are composed of i t ; the bow lders of the fields are largely of i t ;and if a l l these were retur ned to the bil l i t w ou ld be qu ite an interestingproblem to work out how mu ch i ts altitude wou ld be increased .
Then wa lkthrough P lantatlon Street around to a cor responding distance to the north ofthe hi l l and note how r are are the
‘
Mi l lstone H i ll granite bow lders, and eventhesemay be seen to have been artificial ly transpor ted.
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the only one that explains or accounts for a l l these facts”
i sthe last . It pol ishes , makes round , scratches and groovesthe rock surface on the hi l l s and mountains as wel l as thosein the valley over which i t moves , by means of the rockfragments , sand and powdered rock imbedded in its foot ,which materia l i n turn is ground , pol ished , scratched andgrooved unti l i t huds a resting place within and beneath thei ce , or at the glacier
’s end , or is swept away by the streamflow ing from the melting ice . It deposits material promiscuously at its end and beneath itself, and then , overridingit or resting upon i t , compresses and hardens i t . In fact
,
the work done by glaciers exactly agrees w ith the tracksleft by the agent which brought and deposited these domel ike hi l l s of Worcester . Thus , step by step , by thisevidence here in Worcester are we brought to the startl ingconclusion that Worcester was once beneath a thickness ofice sufficient to do al l thi s work , and , from study in otherparts of New England , it i s bel ieved that this ice was notless than a few thousand feet thick , enclosing and overlapping perhaps even the highest mountains in New England .
It here moved from the north , or a few degrees east ofnorth . Within and beneath such a thickness of ice werethese hi ll s accumulated and by such a pressure was theirmaterial compacted .
These dome- l ike hil l s , called druml ins from the 'ael i cdru im ,
” a ridge , are then foreigners or strangers here ,if we cons ider the rock surface the real surface of W orces
ter ; and , i f we would have a perfect picture i n our mindsof this surface , we must remove them . We shall , as we dothis , deprive Worcester of much of her beauty and varietyof landscape , but we shal l be led to other and more ancientstories . But these druml ins are not the only signs andproofs that the ice sheet has left of its occupancy ofthis land .
There were dumped into the many streams within and beneath the melting ice great loads of powdered rock , sand andgravel . These , the streams being powerless to remove , were
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deposited in the val leys fol lowed by these streams , fi l l ingthese valleys to a greater or less extent where they were notalready fi l led by drumlins and l ike material . These , too ,then we must remove in thought as we seek to picture therock surface . There would then remain on the east the
rock ridge already described , incl uding Mil l stone and Paka
choag hi ll s on the west would be the high border of
the rocky highlands of Paxton and Leicester betweenwould be a broad val ley with sl ight inequal it ies about 500feet above sea- level , 200 feet below the eastern ridge , and
500 feet below the western border , gradual ly sloping fromthe highlands of Holden to the south . But this va lley isnot simple ; i t i s div i ded into two , which unite i n thesouthern part of l l
'
o r cester . Commencing with NewWorcester Hill , there i s a rock ridge ri sing 80 feet or moreabove the valley to the southeast , and 40 feet or more abovethe surface of Coes’ pond , and its crest is marked byWoodland and Queen streets . But this , which may becal led a ridge , broadens to the north into a triangular areanot marked by noticeable elevat ions north of Oread Hil l ,but traced by the outcropping ledges beneath AntiquarianHal l , i n Pleasant street'ust west of the j unction with Highland , in Chandler street j ust east of its ju nction with May ,and in Pratt street near Chadwick Square , as it gradual lyrises up to the highlands‘ of Holden . This triangular areai s bordered on the east
'
by Mil l Brook val ley , and on thewest by Tatnuck Brook. val ley . Let us examine careful lythe beds of these streams . We find , where the current israpid , gravel and pebbles ; where slower , sand ; and wherevery slow , only mud or clay . Ra rely if ever do thesebrooks rest directly on the underlying ledge . And if wedig down into these sands and gravel s we find them strat ified or in layers . In fact , these are some of the sands andgravel s from the glacier , deposited by currents of water ,hence their stratified structure ; and these brooks , wearingaway and carrying off during the subsequent time, have
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not been able to lay bare to any extent the ledge underneath . Let us then in imagination remove these gravelsand sands , and w e find that Mi l l and Tatnuck brooks wouldbe fol lowing much wider and deeper val leys than they now
occupy . Exactly the depth of these sands and gravel s weare not able to state , and undoubtedly there i s cons iderablevariation in thei r thickness , as there is in the th icknessof the unstratified glacial deposits upon the hi l l s ; but , i fwe estimate thei r th ickness at from 25 to 50 feet , we probably shal l not far exceed the truth , and it would not besurprising if our estimates were too smal l . Clearing outthese gravel s then , as the brooks wi l l in time , conditi onsremain ing as they now are , and we are able now to form aclear picture of the rock surface of Worcester . A rockridge on the east , high rocky border on the west , a muchlower triangular area i n the middle having a steep slope of75 to 1 50 feet to the east into
'
the ancient Mill Brookval ley , and a more gentle and longer slope to the west intothe valley of the ancient Tatnuck Brook . The ancient Mi llBrook vall ey has a steep slope up the rock ridge on theeast 250 to 300 feet ; and the ancient Tatnuck Brook val leyhas al so a steep slope on the west up to the PaxtonLeicester highlands of 550 to 600 feet . These two val leysjoin at a point south of New Worcester hi l l .Worcester then , in
‘spite of her many hi l l s , i s rea l lysituated in a broad rock val ley with these two smal lerval leys on either side , which join , forming only one in theextreme southern part . We may now ask ourselves ,whence these minor val leys and this broader valley .
The mind may answer , if i t i s not acquainted with geological facts , that these ridges and val leys are due to the foldingof the rock strata , the ridges being the crests , and the vall eys the hol lows of the folds . But as we examine theledges or rock strata from the eastern side of Worcester tothe western , we cannot find any such folding of the rocksbeneath ; we cannot find au v crests for the ridges , or ho l
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lows for the val leys but the rocks consist of layer afterlayer
,stratum after stratum , extending or so , east of
north,by or se , west of south , and tipped up from a
horizontal position 40° and even with the slant
toward the west . As you walk across Worcester from eastto west
,you are real ly stepping on the edges of these
strata . In such strata standing on edges are these val leyssunk
,sometimes paral lel to the strata and sometimes across
them at a smal l angle , now in the harder rock and now inthe softer . We cannot believe , then , that these v al leys aredue to the fo lding of the rock strata ; neither i s there anyevidence to show that the val leys have resu lted from thebreaking of the earth’s surface and the uplifting of theridges and highlands , and the downsinking of the val leys .How then have they been formed ?Last night there was a heavy shower ; the rain fel l i n
torrents ; the waters we‘nt rushing and tearing down the
hil l through the gutters . This morning the sky i s c loudless ; the sun rose in al l its magnificence and glory ; therei sn’t the tiniest brooklet in the gutter to tel l of the roaringtorrent of the night before ; but I notice at quite regulari ntervals along the unpaved street , leading from the middleto the gutter, a large number of l ittle val leys . These aredry now , nor did I stand out i n the rai n to watch eachl ittle brook as it swept along particl e after part icle , andpebble after pebble , thus converting the smooth stree t intoa series of valleys with the ridges between . 'et I am confident that this is j ust what took pl ace . As you watch themadly roaring mountain torrent , swol len by the waters fromthe melting snows , pushing and rol l ing and tumbl ing alongwith i t sand , gravel , pebbles , even bowlders , do you doubtwhence the gulch w ith its steep sides , down which thi sstream rushes ? Neither has the geologist as he studies thecanyon of the West , and sees at its bottom the rapid r iverladen with sand and gravel , every particle of which i scutting into the rock surface beneath as the water pushes
1 7
i t over or dashes it against the ledge , any doubt whencethat canyon . And so as he studies the land surface andfinds these val leys cut in the solid rock , sometimes sti l loccupi ed by rivers and sometimes not, he sees but thehand iwork of some river . And so now , as we see in imagination these rock val leys so largely fi l led by sand andgravel , w hich M i l l and Tatnuck brooks mark out for as,they tel l us of ancient streams , before ever the glaciersmoved over this region , which rose in the highlands ofPaxton and Holden and j oined their waters in the southernpart of Worcester . These streams with their tributaries
,
even to the rain-drops , washed away the decayed rock , andcut down their channels by means of the sands and gravelsthat they carried , unti l they had carved out this broadval ley from the border of the Paxton-Leicester highlandsto the Mil lstone—Pakachoag ridge . But these valleys arenot now j ust as they were l eft by these ancient rivers .During the ' lacial Period the great ice currents that fi l ledand buried them under a few thousand feet of ice andi n whose foot were imbedded sand and roek- fragments
,
rounded them out and deepened them . These val leys arethen somewhat deeper, broader , and more rounded ; butthe ridges were also cut down and rounded at the sametime
,so that the most not iceable effect of the ice invasion
is the round ing and smoothing of the val ley floors.
This broad val ley in which Worcester l ies , i s simply theresu l t of the erosion and removal of material by rivers andice . This valley is but the upper part of the val ley we havealready traced through Aubu rn , Oxford and Webster, whichis marked by the Norwich Worcester R. R. and Lake
Chaubunagungamaug, and which separates the plateau ofLeicester
,Charlton and Dudley from that of Mil lbury ,
Sutton and Douglas . The meaning of this val ley i s thatin former times the land was continuous and of approx i
mately one level from one plateau to the other over thisplateau flowed a river th is ri ver had i ts headwaters in the
2
1 8
highlands of Holden , Paxton and Leicester , and flowed tothe south
,and as it flowed , carved this val ley in this plateau ,
thu s dividing the one i nto two plateaus . But what i s trueof thi s valley i s also true of the val ley in which LakeQuinsigamond lies . It , too , was carved out by an ancientriver . Let us then ' in our thoughts restore what has beenremoved in the forming o f these val leys , j ust as before wecleared out the sands , gravel , clay and bowlders that theice left in them . But now we must fi l l i n with rock mater ial l ike that beneath and as each rock stratum stands oni ts edge , slanting to the west and extending 30° east ofnorth
,we must think of these rock- strata extended upward
unti l their upper edges constitute a plain on a leve l withthe Paxton-Leicester highlands on one side and with thetop of Mill stone-Pakachoag ridge on the other , as thesew ere before they were planed down by the ice of the glaciers . In like manner let a s think of the val l ey of LakeQuinsigamond as being fi l led by the upward projection ofthe strata of i ts floor , so that the land is continuou s and ofone leve l across from Millstone-Pakachoag ridge to thehighlands of Shrewsbu ry .
This plain would have a gentle slope to the east and agentle slope from the highlands of Holden to the south .
This pla i n wou ld be higher than the present plai n join ingthese areas by as much as these highlands and ridges werelowered by the erosion of the ice . This i s an unknownquantity , but was probably not equal in a l l places . Probably such a narrow ridge as the Mil lstone-Pakachoag ridg ewas lowered considerably more than were the broader areasof Paxton and Leicester . This being so ,
the p lain that weare reconstructing would not have as great a slant to the eastas the pla in join ing these as they now are would have .
That ancient plain probably had a slope of less than fiftyfeet to the mile , but that it sloped to the east i s i ndicatedby the fact that the highlands of Shrewsbury on beyond arenot so high as are those of Paxton .
1 9
Let us then t ake our position upon th is broad plain,standing . 400 feet above the Common , and look around .
The'
_highlands o f Paxton and Leicester are but a l ittle above
us, and the slope i s so gentle that we should cal l the surfacea plain w
,e should be a l ittle higher than the high lands ofShrewsbury, ,but
'
again the difference is by such a gradualslope that We. may call it a plain ; and
' i n l ike manner fi l l ingin the old river valleys to the north and south , and to theeast and west , as we have those of Worcester , there wouldbe a broad plain with but sl ight inequal ities . Looking atthe horizon a round us Whi le s tanding on that plain , it wouldbe almost the perfect circumference of a circle . To thesouth this plain would include the plateaus already pointedout of Mi llbury , Oxford , Sutton and Douglas , and ofCharlton and Dudley ; to the west i t would include thehighlands of Leicester and Paxton , al l save Asnebumskit ,
’
which would ri se fully 400 feet above our newly constructedplain . As we fol low this plain to the north , i t incl udes al lthe highlands of Holden , Rut land and Princeton , exceptthe roek-mass of Wachusett and Little Wachu sett . Thi srock-mass , rising at its h ighest point a thousand feet abovethis plain , i s certainly not a part of i t . We thus see thatwe should be standing in the midst of an ancient plainsloping to the east and the south that was before these riverval leys were cut , and above
'
and out of which rises now andthen an eminence l ike Asnebumskit , Wachusett , and , sti l lfarther north
, W atat ic and Monadnock . This plain is theancient peneplain of Southern New England that Prof. Wm .
M . Dav is so clearly and graphical ly points out ' to us.
1
These eminences'
r ising above the plain he call s Monadnocksfrom the typical one in southern New Hampshire .
We have spoken of this ancient peneplain as sloping
i bove Worcester towards the east and the south . This wastrue i n a general sense , but local ly this plain sloped muchmore decidedly to -the south , for the old river val leys run
1 The Physica l 'eography of Southern 'ew 'ngland.
20
approximately north and south , showing the direct ion theseold rivers took as they began , if we may so speak , to flow
over or down this surface . But we cannot speak of therivers as beginning then , for the r ivers were much olderand fol lowed the slope of the land of an earl ier time . Thismay possibly ind icate a slight change i n the relative position of the land immediate ly about us— a l owering of thatto the east or an elevation of that to the west .Leaving now , for the time being , thi s old peneplain withits Monadnocks ri sing above i t , let us examine some fact sabout a s that may prove of interest , and that may have abearing upon this . Let us go to the quarries on M il lstoneHi l l . The rock is of a somewhat coarse , crystal l ine texture ; i s composed first and largely of nearly white feldspar ; second , of l ittl e rounded masses of smoky , sometimesblue , quartz ; and , third , of smal l black fol iated masses ofbiotite mica . If we search careful ly through the quarrieswe may also find a smal l amount of beryl , some mo lybde
nite , and fluor i te especially on the surfaces of fissures .
These last minerals we immediately recognize as not essential constituents of the rock . We also notice that the rockhas no layer or fol iated st1 uctu 1 e . It is perfectly massiveand homogeneous . If we trace this rock in any direct ionWe find that it is local , does not generally extend even tothe bottom of the hi l l but other rocks of gray
,drab or
black color appear in the outcropping l edges . These rocksaround the base and reaching up on the sides of Mil l stoneHil l we recognize as very different from the rock at the top .
They have a layer structure , the ir substance is arranged inlayers or strata , and the strata lean towards the hi l l on thevarious sides except the southern . A l so
,i f we careful ly
examine the quarries at the top , we see a few sheets or thinmasses , la id bare by the removal of the rock by the quarryman , closely resembling the d ark drab o r black rockaround the base , but appearing as if they had been heated .
These sheets are or were included in the mass ive rock first
21
described . Taking al l these facts into consideration— thedislocation of the neighboring rock , the incl usion of fragments of the neighboring rock , the massive crystal l inestructure , and the composition— we concl ude that the rockof the quarries i s a granite . It i s a foreigner , as it were ,here , and came into its place after the neighboring rockswere already in place . It w el led up from beneath asmolten rock through some opening or fissure, and the dislocation of the neighboring rock accompanied the well ingup of molten rock . Hence it is that the neighboring stratalean against the granite mass . This rock quarried on Mi l lstone Hi l l is then a granite . But gran ite has a story to tel la s. By i ts coarse crystal l ine texture , by i ts entire or com
plete crysta ll ization , by the l iquefied gases held in cavities
within i t , the granite tel l s a s that i t did not sol idify andcrystal l ize at the surface of the earth where it now is , butat a great depth beneath the surface . Rocks sol idifying atthe surface take on the form of the various lavas ; are l ikelyto be spongy or porous , glassy , and only partial ly crystall ized . These characterist ics the granite does not possess ,but others pointing to a slow cooling in some buried depth .
There i s also the rock quarried at the Bal lard quarry nearQuinsigamond . Examining this , we find nothing resembling the rock found at Millstone Hil l quarry . Here al l ofthe rock substance is arranged in layers ; and we may tracethese from one end of the quarry to the other , forming wavybands of various tints . Some are almo st white and ofcoarse crystal l ine texture some are light gray and of fiuecrystal l ine texture ; some are greenish gray and also fine
some are of a darker gray and present a streaked appearance , and have a medium coarse crystal l i ne texture ; someare hard and fi rm ; some soft and easi ly crumbled . But inal l of this variation there i s one characteristic in common ,al l are crystal l ine . These bands have a direction of about30° east of north ; and where they rise into the wall s of the
quarry , are seen to be but the edges of strata ti lted from
22
a horizontal position to an angle of about 75° slanting
towards the west . These strata were not always as theynow are . They tel l us of a time when they were not crys
tal l ized , of a time when they were deposited in the watersof an ancient sea as impure layers of sand , impure layers ofcl ay, or possibly layers of pebbles along some beach ;some of these layers were col ored red or yel low by i ronrust
,or possibly black , from the particles of magnetite dis
tributed through them ; others were white as the sand of
the beach . But between these two stages - of these rockstrata
,the present w here everything is crystall ine and the
former where everything was fragmental , there has been awonderfu l change . Subjected to the action of hot watersunder pressure , and waters sat urated with mineral substance because they were hot and under pressure , thesefragmental strata have been sol idified and recrystal l ized intotheir present condition . But these are changes that do nottake place at the surface of the earth , but at considerabledepths within the earth . We might also consider the otherrocks found about us from M il lstone-Pakachoag ridge toand including the highlands of Leicester and Paxton ; al lwould tel l the same story of a transformation that could nothave taken place at the surface of the earth .
What does al l thi s mean ? Simply that these rocks nowat the surface of the earth were once buried beneath somethousands of feet of rock . It means , were al l the rockmaterial here that once was here , the land here would benot l ess than 5000 feet above the sea- level instead of 500 .
And this i s true not only of this immediate region but al soof Southern New England in general . Above this peneplainthat we have asked you to observe as you looked to thenorth , south , east and west , the rocks were extended fullya mile . But where is al l of this rock material ? Whitherhas al l this rock material gone ? It has gone just as thesand and clay are swept along by the brooklet . Duringthe long ages of geologica l time after this land was raised
23
above the sea , the agents of the atmosphere , the rivers andthe rivulets , the brooks and the brooklets , were softeningand loosen ing and removing particle after particle
,unti l
this whole mass was carried off and cast into the sea to formnew lands beneath the sea . But is it possible that al l ofthis great rock mass has been removed and not a vestige ofi t anywhere remains ? Look yonder at Asnebumskit , Wa
chusett , Watatic, Monadnock . They are what remain ofthis great thickness of rock to tel l us the story . The rocksaround them have been removed while they have escapedthis great erosion . But why did these points escape ?Why was Wachusett left while the broad surrounding country was r educed ful ly a thousand feet beneath it ? The fi rstthought that comes is that it must be composed of so muchharder and more resi sting material that the elements werenot able to reduce it as they reduced the surrounding country . Let us examine the rocks of Wachusett w ith this inv iew . It is composed of gran ite with a smal l amount ofmica sch ist appearing at various alt itudes ev en to the top .
The granite i s no more resisting than is that of broad areasaround that have been reduced to the general level of thepeneplain around its base . The mica schist is soft andeasi ly worn away . Then , surely , to say that i t standsthere because of its greater resisting power is but apoor answer to give . And if we look to Asnebumskit ,such an answer is less valid . It i s composed of a soft micaschist , much softer and less enduring than much of the rock
in the val leys beneath . There must be some other. princ iple that explains these remnants of th is old land mass .
Let us picture in mind a land area for the fi rst timeexposed to the action of running water , a lawn , i f you w i l l ,that the gardener has prepared for the seed . As the rainfall s in the spring shower
,the drops , guided by the l ittl e
inequal ities , gather into ri l l s , the ri l l s into brooklets , andthe brooks cut out thei r val leys in the soft ground . There
are two brooks approximately paral le l ; between them is a
24
ridge,and the crest of the ridge is the divide between these
streams . If we examine the water as i t begins to movefrom this divide
,the streams are the minutest possible ;
they can do but the feeblest work ; but when the manydrops have swol len into the rushing brook beneath , eventhe large pebbl es are pushed along . That ridge stands be
tween the two brooks because of the inequal ity in theerosion . The crest of the r idge is a l ine of less- erosion ,therefore that l ine i s the highest l i ne between the brooks .
But again let us think of two tributaries flow ing side byside down the right hand slope of this r idge into the righthand brook . Each of these i s cutting its val ley , and therei s a divide between these . The crest of this ridge , slopingthough it may down towards the main stream , i s aga in al ine of less- erosion with reference to the channel s of thesetributaries . The left hand stream al so has two tributarie sflow ing down the left hand slope of the main ridge , andthese tributaries are approximately opposi te t he right handtributaries . Between these is also a l ine of less- erosion .
These two l ines of the second order of less -erosion meet theli ne of less- erosion of the main ridge at approximately thesame point . W here these l i nes of less- erosion cross i s apoint of less- eros ion . There W il l be many of these pointsof less- erosion along the ridge ; and as we fol low the ridgein the direction of upstream , these points wil l he points ofl ess and less erosion unti l up at the very sources wi l l be thesuperlati ve , the point of
‘
least erosion in the degradation ofthat country up where the great divides between the mainstreams of the country cross . In other words
, Asnebum
sk it , Wachusett , W atatic, Monadnock , are the points ofleast— erosion in the degradation of Southern New Englandto this broad peneplain .
As we have in a former part attempted to picture thepast condition about as by fi l l ing i n the val ley in whichWorcester l ies , so now let us bring back al l of this rockmaterial that has been removed so that these r ocks now at
26
At many points cleavage is more or less perfectly developed
in the finer grained rocks .The crushing forces that caused §the greater and smal ler
deformities cannot have been exer ted '
after the penepla inwas
-produced,for in that event they would have deformed
the upland surface . The deformation of New Englandmust have taken-place beforetheg reat denudation . Duringthe p eriod of most energetic deformation , New Englandmust have had as thoroughly a mountainous form as it sti l lhas
'
a mountainous structure . Indeed , the most probableconcl usion that can be reached regarding the ancient topography of the region , raises its peaks to truly Alpine heights ,clothes their upper slopes with snow- fields, and fi l ls thei rval leys with glaciers ; and al l these features should berestored in the p ictures
'
tha t the attentive observer mentallysketches in his effort to represent the ancestry of the upland .
Very slowly were the ancient mountains rai sed much moreslol were they worn down , unti l now only their baseremains . New England is a w orn- out mountain range .
The ful l meaning , then , of what the granite of Mil lstoneHi l l and the upturned layers of gneiss at the Quinsigamondquarries and the crystal l i ne schists east and west of W orces
ter tel l us i s that once in distant ages of geologic timethey were the foundations of lofty mountains .As we fi rst pictured the su rface of Worcester as it i s
,
then as it was before it was modified by the glaciers , thenas a part of the broad peneplain of Southern New England ,so now we must bring back and build up these majesticmountains , the lost glory of 'ew England . Compared withthese Wachusett , the p ride of Worcester County , i s themerest pigmy . It too was in the foundation of theseancient mountains , for the rocks at its summit tel l but thesame story of having been buried far within the earth .
Considerable has already, been said in regard to thewater—courses of Worcester , but let us consider in detai leach , commencing wi th the most easterly , Lake Qui nsiga
27
mond . This is a type of the beautiful sheets of water thatnestle here and there among the hill s of New Englandr el ieving the monotony , and adding beauty and refreshmentto the landscape . These ponds or lakes occupy naturalbas ins , and are very important in the natural economy .
During the dry months of the year , the water soaks intothe surrounding earth , refreshing and enl i vening the vegstat ion from them also moisture passes into the air , cool ingthe atmosphere and rel ieving its dryness ; and as the waterin these basins i s lowered during the dry months , theycatch and hold back the floods of fal l and spring so that thelowlands of the river val leys are much l ess devastated andoverflowed . They are , in fact , but the local broadeningand enlarging of the channel s of the various brooks andrivers in whose courses they occur . As the stream seeksthe sea over an i rregul ar surface , it meets w ith obstr uc
tic’
ms around which it cannot flow because of the surrounding elevations ; or the river flows into a bas in , and in thisbasin the water accumu lates ti l l i t reaches the lowest pointin the rim ,
and then at this point the waters flow out .Here is a lake , But no sooner does the water begin toflow over the rim , be the material beneath of sol id rock orof loose materia l l ike bowlder clay , than does the swiftcurrent begin to pick up particles of the rock or clay , andsweep these along , thus wearing away and cutting down ,lower and lower , year by year , the outlet . Thus the lake
is gradual ly drained .
But there i s another side to this story . At the head ofthe lake and along its shores , wherever there are rivulets ,brooks
,or even brookl ets l iv ing but du ring the continuance
of the rain- storms or showers , they are bringing in the irloads of sand and clay , and depositi ng them in the quietwaters of the lake
,the coarser at the immediate mouth of
the stream and the finer out in the deeper waters over thewhole lake—bed . Thus it is that , however muddy and dirtythe water that enters these lakes , that leaving wil l be clear
28
and free from sediment . And so as the years go by thebrooks and rivers build out thei r deltas , the lake- bed israised l ittle by l ittl e , the lake is contracted and madeshal low
,vegetation springs up and adds its substance to
the fil l ing material , and the basin is fi l led ; so that even ifthe outlet i s not cut down so as to drain the lake , sti l l the
lake is doomed to obl iteration , first becoming a marsh andthen a meadow with the stream winding through it in aserpentine channel . Lake , marsh , meadow are the stagesin the history of every one of these sheets of water .When now the meadow is overflowed by the floods ofspring , i t simply tel ls a s of what was once there . Andduri ng these flood periods the work of former times is simply continued , for these waters are laden w ith mud andsil t which settle and bui ld up the meadow a tr ifle each year .Thus the work goes on unti l the meadow is bey ond thereach of the highest flood , or is drained dry by the cuttingdown of the outlet . Long hence may the time be whenthe rivers , following immutable law , shal l have removedthese many jewel s of New Engl and scenery ' The veryfact that so many of these natural ponds and lakes remain
,
tel l s a s of the shortness of the time in w hich these streamshave been cutting away obstructions and fi ll ing basinswithin their courses ; tel ls a s that these streams have beenfollowing these courses but a short time , are in fact in thei ryouth . Thus are we able to speak of the age of brooksand rivers ; by the work accompli shed we may know theyouth , the middle-age , and old age of streams .We poi nted out in the ease of Mi l l Brook
,how it i s
flow ing over gravel s and sands deposited in an old'
riverv al ley . Se quite general ly the streams about as are following old river val leys that had been cut i n the oldpeneplain of southern New England before the glacialperiod ; but during the glacial period enormous quantitiesof sand and gravel together with unstratified drift weredeposited i n these , partial ly fi l l ing some , completely obl it
29
crating others . Thus it is that waters of subsequenttime have sometimes fol lowed the old valleys irregularlyfi l led , or have sought out entirely new courses . In eithercase basins and obstructions were encountered in which
,
and behind which , the waters accumulated , forming thelakes . Thus we see that the glacial period made out ofthis region a new land surface . It was a re- creation in'ew England landscape . This landscape about us has thev igor , the freshness , and the beauty of youth .
Return ing now to Lake Quinsigamond , these laws arebeing executed in this lake as in others . The time w i l lcome , j ust
’as surely as the rain fall s and the brooks flow ,
when this beautiful sheet of water , on whose shores theIndian bui lt his W igwam , and by w hich the early sett lerswere attracted to fix the site of our prosperous and beautiful city , wil l disappear from the face of the earth , and inits place wil l be a long , narrow meadow , through whichwi l l laz i ly flow , w i nding along in its serpentine course ,an insigni ficant river .Lake Quinsigamond i s about five and one- hal f miles long ,
and,in the upper part , one- eighth to one -quarter of
a mi le wide , and in the lower part about one mi le wide .
Through a large part of its cou rse it might be taken for awide
,slowly moving river . It i s 360 feet above sea— leve l
and 1 20 feet below the Common . It fi l ls a smal l part of agreat rock val ley lying between Mil l stone Hil l ridge and
the high rock ridge extending through the southwestern ,western
,and northwestern parts of Shrewsbury . This
val ley is in w idth,measuring from crest to crest of these
two ridges,two miles and more in places , and in depth ,
measuring to the surface of the lake , 400 feet . In fact thealtitude from the lake to the highest point on M i l l stoneHil l is greater than the elevation of the lake above sea- leve l .
But the lake does not rest directly on the floor of the rockval ley
,but on sands and gravels twenty-five , or perhaps
fifty , feet thick . This great rock vall ey is then probably
30
500 feet deep . This val ley , l i ke those al ready describedwest
'
of Mill stone Hi l l'
r i dge, i s an old river val l ey , whichwas rounded ou t and '
d eepened by the ice of the glacia lperiod . The floor of this val ley is cover ed
'
by a layer orcoating of varying thickness of sandsa nd gravels . Theseal so belong to theglacial period , and were left there duringthe l atter part of that period . These sands and gravels areseen on either s ide of the lake , and extend some distancefrom i t . In places there are great cavities sunk in thesesands and gravel s , and some of these hold l i ttle lakes ,which rise and fal l with the w ater in Lake Qu insigamond . There are real ly What we may cal l ‘ two lakesin th is val ley . The one that we see and cal l Lake Qu insigamond is by far the smaller . Let a s th ink of this body ofwater , and then think of the sands and gravel s beneathand on either side as perfectly dry how long would LakeQu
’
insigamond remain in v iew ? Evidently in a very shorttime its waters would disappear in these sands . Thenthese sands must be permeated or soaked with water
,water
fi l l ing the spaces among the grains . In other words thereis another Lake Quinsigamond broader and deeper thanthe one we know , as broad and deep as are the sands andgravel s of this val ley . The l ittle lakes in the cav itie sal ready described simply reveal to us the level of th is lakethe cavities are deep enough to reach down below the leve lof this invisible lake , and hence the waters appear in them ;
and the rising and fal l ing of these l ittl e lakes are but therising and fal l ing of the great inv isible lake within thesands and gravel s .On
’
the shores of a similar lake in W ebster , Lake Chaubunagungamaug , there have been sunk wel ls i n the sandsand 'gravels , from which water is pumped with which tosupply the town . These wel ls have been sunk into theinvis ible lake . The pumps are simply drawing water fromthe greater lake , whose waters permeate the sand and graveloccupying that rock val ley . And so by boring into thesands and gravel s bordering Lake Quinsigamond
,at
31
approximate ly the l evel of the water in the v isibl e lake ,the waters of the invi sible lake would be reached . We
may hereafter , as we look at Lake Quinsigamond , remember that deeper and broader lake of which it i s only the
vis ible part .We have spoken of th is great rock val ley in wh ich Lake
Quinsigamond is , as the val ley of an ancient river . If i t is
such,we may rightly ask why the waters accumulate to
such an extent here . Simply because a t North 'rafton ,at the foot of the lake , a large mass of firm , hard , compactglacial material was left , as the glacier retreated , fi l ling theval ley so that the valley i s almost obl i terated . This ma
ter ial i s so compact that the waters cannot leach through itto any extent , and so the waters accumulate back of it ti l lthey rise high enough to overflow thi s barri er as they doin Quinsigamond ri ver: But while we can easily see wherethe barrier is that holds back the waters and of what i t iscomposed , there is something else not so easily explained .
We have spoken of this old rock-val ley as being partial ly
fi l led with sand and gravel . The surface of the grave l s onone s ide of the lake is on a l evel , approximately , with thesurface of those on the opposite side , whi le in the midst isthe depression of the lake . The question which we desireto answer is thi s Why are not the gravel s that appearon ei ther side of the lake continuous across the val ley
,
thus completely fi l l ing the depression now occup ied byLake Quinsigamond ? Why was not the central part of theval ley fi l led up to the l eve l of the gravel on either side ?Standing at the middle of the causeway that crosses the
lake and look ing north or south , we see that the shores areeverywhere composed of gravel the surface of thesegravels is not a regular plain , but rises in knol l s ormounds resembl ing inverted cups , and descends in saucerl ike depressions among these knoll s . Also we see distr ibuted here and there in the midst of the lake itself, i slandsrising a few feet above the surface of the lake
, and composed of gravels l ike those in the shores . Whatever
32
explanation makes clear the origin of the gravel s in onemust make clear that of the other . How , then , may wethink of this depression within the gravel that i s now occu
pied by Lake Quinsigamond as having been formed ? Letu s think of the great val ley between the Mil lstone ridge andthe Shres u ry highlands as be ing fi l led with the ice ofthe glacial period from rock su rface on the east to the rocksurface on the west and from the rock-floor to the top ofthe enclosing ridges and beyond . This val ley was a riverval ley before that and not of un iform depth . Where theancient river was ju st before the glacial period must havebeen the deepest part of th is val ley . In other words
,the
river followed a channel in this val ley below the floor ofthe val ley on either side . The depth of this channelbelow the valley-floo r would depend on the veloc ity of theriver current . If the land of this vicinity
,in common with
al l New England , was greatly elevated before the coming ofthe glacial period , as is qu ite well establ ished , then thisr iver was moving with a rapid current
,and may have
,
probably had , lowered its channel considerably below thegenera l floor ' of the valley . This channel would underthese condit ions have steep sides and would be a canyonw ithin this val ley . Then the ice fi l l ing thi s va lley musthave been of varying thickness , being thicker where theval l ey was deeper . Let a s now think of the last stages ofthe glacial period , when the ice was melting away and disappearing fr om the land about us. As the ice melted therewere abundant streams , some upon the ice , some fol lowingtunnel s within the ice ; and those upon the ice must havepassed down into the ice whenever a fissure crossed thecourse of the stream . But as the ice became thinner andthinner and its motion became less and less in the clos ingstages , the streams on the surface must have become moreand more persistent , disappearing less and less frequently .
These streams were abundantly suppl ied with sands andgravels which had been held within the ice . The streamswere not able to remove these entirely
,and so distributed
33
these sands and gravel s over the surface of the ice , buryingthe i ce under a thick covering of sand and gravel . Thi scoating came to be many feet in th ickness as lay er afterlayer was spread over the surface . Also this coating wascontinuous across the area over wh i ch it was spread , andits surface constituted a plain without noticeable depressions or elevations l ike those in these sands and gravels atthe present time . But the ice buried beneath these gravel sand sands was of varying th ickness , being thickest abovethe river channel in the old val ley ; so that as this icemelted , the gravel s and sands sank unti l at last they restedon the rock-floor beneath . Where the old river channe lwas , there the sands sank lowest , and thus left a long ,narrow channel- l ike depression , bordered on either side bysands and gravel s , with a steep slope from their surfacedown into the depression . But even the ice within thesands and gravel s on either side of this great depressionwas not of uniform thickness , and so as this ice mel tedthese sands and gravels were left with an irregular surfacebroken
_by hi l locks and saucer - l ike depress ions . The
islands distributed here and there through the lake mayhave been caused by sand and gravel accumulating in
smal l local depressions in the ice , thus giv ing a greaterthickness of gravel and a smal ler thickness of ice beneath ,so that as the ice melted these fi l led depressions were lowered less than the surrounding gravel s , and so ri se abovethem
,and appear even above the waters of the present
lake . Thus may we interpret the facts presented to ourv iew as we look to the north and south over that beaut ifulr iver— l ike lake , Lake Quinsigamond .
But le t our thoughts now return to the rock val ley inwh ich this lake l ies . Let as remove in mind the sands ,gravel s , and lake , that we may think '
of the region as itwas before it was mod ified by the glacial agents . It was abroad
,deep val ley
,two m iles or so in width , and 500 feet
deep , and with sides less rounded than now . In this val ley
flowed a river , and a much more powerful river than those3
34
already spoken of west of Mil lstone Hi l l ridge . Th is river
flowed to the south , and fol lowed , approximately , thecourse of the Blackstone— in fact was the ancient Blackstone . To the north we are not as yet sufficiently wel lacqua inted with the country to trace this val ley , but it wi l lnot be su rprising i f th is valley is traced and found to jointhe vall ey of the ancient Nashua River . Whether this beso or not , i t was a powerful river and of considerablevolume , for it cut its channel a hundred feet or more belowthat of the ancient Mi ll Brook , and that too in harder andmore resi sting rock . Let a s fix this fact in our
' minds,for
from this has resulted a very important fact in regard tothe drainage of Worcester .In describing the Millstone-Pakachoag ridge it was intended to make special ly prominent the breaks or cuts ini t , especial ly that through which flows the Blackstone . Ifwe examine the region including New Worcester
,South
Worcester , 'amesv i lle and Stonevil le , we find fi rst
streams flow ing from the north , as Kettle , Tatnuck , andMill brooks ; then those flow ing from the south , as thatfrom Ramshorn Pond and others from the foot of Pros
pect Hil l in southern Auburn . These two sets of streamsfi na l ly j oin and constitute the head-waters of the Blackstone . Ano ther fact that must arouse interest
,i f we
but stop to th ink , is the winding course of Kettl e Brook asit fol low s its circu itous route from 'amesvil le to Stonev i l le , thence to Curtis Pond , and then to South IVorcester ,fina l ly reaching the gateway of the Blackstone .
Thesefacts demand ou r attention and some explanation
,especial ly
when we compare this drainage arrangement with theFrench River ju st west and the Blackstone j ust east . TheFrench River flows from the north to the south ; the rea lBlackstone , or original Blackstone , including Lake Quinsigamond val ley , i s from the north to the south ; but thedrainage from Mi l lbu ry and Auburn into Kettle Brook
,
approximately paral lel to these , i s from the south to thenorth . The meaning of this pecul iar arrangement of these
35
streams entering Kettle Brook i s this : Long before theglacial period there was an ancient river , which we havecal led the Auburn River , which rece ived the waters of theancient Kettle , Mil l and Tatnuck brooks . The two latterbrooks flowed together at a point a l ittle south of NewWorcester , while Kettle Brook joined them at a point a l ittlefarther south , possibly at Stonevi l le . This river did notflow through Quins igamond Vil lage and thence to Mil lbury ,for there was not then any deep cut through the Mi l lstonePakachoag ridge as there now is ; but this ancient riverflowed down through Auburn , east of Prospect Hil l ,through Oxford Plains , thence into Webster , cutting outthe val ley now partly fi l led by Lake Chaubunagungamaug .
This is the val ley that was poi nted out in the early part ofth is paper as separating the highlands of Mil lbury , Oxford ,Sutton and Douglas on the east , from those of Le icester ,Charlton and Dudley on the west . In fact , thi s valley , thehighland borders of which we have already traced , was cutout by this ancient river in the old peneplain of southernNew England . But the continuation of this vall ey inConnecticut we are not yet able to trace from l ack ofknowledge of the country . The head- waters of this ancientriver were separated from the waters of the ancient Lake
Quinsigamond River by the Mi l lstone-Pakachoag ridge ,which was then continuous without the cu ts through whichnow pass the Boston and A lbany Railroad and the Blackstone River . O f these two ancient streams the LakeQuinsigamond River was by far the more powerfu l andwore away and lowered its channel much mo 1 e rapidly thand id the head- waters of the ancient Au burn River . TheLake Quinsigamond River had tributaries, both large andsmal l , and as the main r iver cut down its channel , so a lso
did they cut down theirs . One of these tributaries flowedfrom the eastern s ide of Pakachoag Hil l through what isnow Mil lbury
,and joined the main stream at approx i
mately Farnumsvil le . This stream was in i tself qu ite a
powerful river , and it cut its channel lower and lower into
36
the highlands of which Pa'
kachoag and Vernon Street Hill sare now the western border. A s i t di d se , i ts head- waters ,even to the tin iest
'
brook , were cutting into these highlands . There appeared fi rst the merest depression between
these two hil l s . Thi s was made deeper and deeper , andthe head-Waters of
i
thi s tributary approached nearer andnearer to the ancient Mil l Brook on the other s ide . At
last,at a time when the ancient Mi l l BrOok was swollen by
floods, i ts wafers began to ,
flow into this tributary , and
ceased to be apart of the Aubum -.River Thus it was that
the deep cut' between Vernon Street and Pakachoag Hills
was made Thu s it was that Mil l Brook began to flow
down through Mil lbu ry , while Tatnuck and Kettle brookscontinued to flow down through Auburn .
1 But the same aotion going on would have i n time diverted fi rst Tatnuck , andthen Kett le Brook 1 n the same way . But the turning ofthese: or at least the last , into the Blackstone , togetherwith the waters from Ramshorn Pond in Mi llbury and thewaters from the northern slope of Prospect Hil l in Auburnahd Oxford , was brought about in another . way . Therecame the time when the land was covered by the great ' icesheet . Because of this , after the departu re of the ice , theval leys were to a greater or . less extent fi l led with sandsand gravel s and unstratified glacial materia l . Some valleyssuffered in this respect more than others . While somer ivers , after the departure of the ice , continued to flow overthe sands and gravels in some of these valleys , in the caseof others the rivers ceased ent irely to flow as they hadformerly . This was true of the Auburn River . The sandsand gravel s and other glacial material were deposited sothickly in this valley between North Oxford and Auburnas to form a low water- shed , and thus the waters in theval ley north of this were forced to flow to the north
,and
,
joining with the waters of Kettl e Brook , fina l ly found an
1 It is hoped that the good people of M i l lbu ry w i l l not now apply for an
in'unction to force tli e City of Worcester to change the course of Mi l l Brookinto its ancient channel .
37
outl et into the Blackstone . As we thus read back step bystep , we find one fact after another explained , and we nowunderstand the circu itous path that Kettle Brook fol lows ingetting out of th is enclosed basin on its j ou rney to the sea .
'oing to the west the next considerable stream is thebrook flow ing through Peat Meadow ,
Beaver Brook . Thisrises among the drumlins of the sou thern part of Holden ,and flows approxi mately south , with drumlins on eitherside of it through nearly the whole of i ts course , ti l l i t addsits waters to those of Tatnuck Brook . There is no indication that this brook fol lows an old river or brook v al ley ,but its course has been entirely determined by the deposit ion of the glacial dri ft , which is for the most part in theform
'
of druml ins . This brook had its beginning with thewithdrawa l or retreat of the ice of the glacial period fromthis region . It was original ly a brook or river carry ing offthe water from the melting ice that enveloped these drumlins , and since then the waters that have fallen upon thesides of these have been sufficient to keep water flow ing i nthi s channel even during the dry months of the year . Bu t
the valley formed by these many druml ins on either sidewas quite i rregular ; there were depress ions i n it and ob
str uctions across i t . The depressions the waters fi l led , andthe obstructions the waters overflowed , i n ei ther case producing an accumulation of waters , thus forming ponds .Into these ponds the ri l l s and brooks from the neighboringhil l sides , swol len by heavy rains and spring floOds, flowed ,bearing the ir loads of clay and sand . Vegetation sprangup and grew luxuriantly in the moist rich soil spread overthe bottom of these ponds , and thus the shal low basi ns wererapidly fi l led . And so these basins were transformed intomarshes and meadows , which we find through a large part ofthe course of this stream . Peat Meadow is such a marsh ,which was once a shal low pond . This brook has al so re
moved large quantities of sand and gravel , and has made adeep out between Pleasant and Chandler Streets . Alongthe western side of this out there remains a beautiful ter
38
race showing the former height of the land across thisval ley . Had not the brook , as it was c utting away here ,been interfered w ith , i t wou ld in time have cut into PeatMeadow and drained i t , leaving i t high and dry . Thus therear e within Worcester i l lustrations of a stream in its youthwhere the lakes and natural ponds have not yet been fi l led
up because of their depth and size , and of a stream in itsmiddle l ife where these have been fi l led and almost drained .
In the extreme western part of Worcester is the succession of ar tificial ponds from Tatnuck , or better , from theHolden Reservoi r , to New Worcester and the south . O u
the early maps of Worcester this i s but a simple streamflow ing thr ough this valley , but at later times dams werebuilt acro ss the val ley at various places to hold the waterback to be used for power, or to be stored up for useduring the dryer months of the year . The present streamhad its beginning when the glacier withdrew from thisregion , carrying off the abundance of water from the mel ting ice . But before ever glacier covered this land surface
,
enveloping both hil ls and val leys , there was a river flow ingdown through this vall ey , as we have already pointed out .If you desire to see a perfect il lustration of an ancientriver val ley , go to the summit of Pakachoag Hil l lookingto the northwest you w i l l see the horizon resting uponAsnebumskit , then sinking abruptly to the level of HoldenReservoir , then rising by an almost verti cal l ine to the summit of Stone House Hil l . This notch in the horizon i s notunlike the notches produced by the canyons of the West
,
though on a smal ler scale the wal l on the one side ri singover 300 feet , and on the other side 600 feet above the reservoi r . And then , as you walk or ride along the shores ofthat reservoir , recal l what that deep gorge te lls of the past .It i s the val ley of an ancient river .But to return to the present— this stream ,
converted intoa succession of ar tificial ponds , i l l ustrates the manner inwhich man has interfered with natural processes . Left toitself, thi s stream would go on clearing the sands and
39
gravcls out of thi s o ld river val ley , especial ly when it i s
transformed into a ru shing torrent by the melting snowsand heavy rains ; but by these ar tificial basins its waters a restored up in times of flood ; i t ceases, to be a torrent , andbecomes a more gentle and uniform stream throughout theyear . But its abil ity to do geological work is thus greatlydiminished . For oftentimes in the flood
°
per iod , b ecause ofthe greater volume of water and the increased velocity ofits current
,the stream does more work than during the
remainder of the year . Moreove r , through these pondsthe current of the stream is very slow , and its abi l ity tocarry material and cut down i s reduced to zero ,
‘ so that theerosion of the stream is limited to the parts of the channe lbetween these ponds . But even here the stream is al lowedto expend but a smal l part of i ts energy without inter fer
ence . It i s caused to fall over a precipice on hard andresi sting rock placed there to receive the blow , or it m ustwaste i ts energy , geologically , tumbl ing down a series ofsteps a l so of enduring rock . These rocks are r enewed byman as fast as they are worn away . But this only appl iesto the part of the stream that i s al lowed to go over the dam .
By far the larger part is forced to move wheel after wheel ,each of which moves scores of feet of shafting , and thencethe motion goes into machines of every description , thecunning devices of men to take from that stream its storedup energy and make it do work other than that whereuntonature set i t . For a river i s able to do only a certain quantity of work . It i s a fall ing body , and possesses a fixedamount of energy because of the posi tion of i ts watersabove the sea . In flow ing along in its natural state theriver i s pushing and rol l ing along pebbles , i s taking up andcarrying along bodily grains of sand and particles of clayand so close ly does the river attend to its task that when i treaches sea- l evel i t has barely energy enough left to crawlthrough its winding course at base- level and lose itself inmother ocean . Then so much of this energy as i s used up
in turning myriads of wheel s cannot be used in doing i ts
40
geological work , the clearing out of this old river val ley .
But man does not have it al l his own way in this matter .
He who seeks to thwart the course of nature must make nomistakes in his calcu lations . For i f he fai ls to calculatearight the power of that stream when the water i s high , hiswork i s swept away
,and the devastation below , the geo log
i cal work,i s al l the greater r or if he leaves a crack or
crevice in the obstruction , the waters wil l find i t andcommence their work of enlarging and weaken ing , whichmay result in the downfal l of the whol e obstruction . But
suppose man makes no mistakes , sti l l that river i s morethan his equal . The river , aided by al l the brooks flow ingi nto that pond
,and by vegetation along its shores and i n the
shal low waters,wil l fi l l that basin . What then wil l hold
back the floods of spring ? O f what use wil l the dam bewhen
'
the m i l I- pond is a marsh ? Study the mi l l-ponds seenas you fol low the French and the Blackstone Rivers on yourway to Norwich or Providence , and you w i l l see that thisis what is taking place . So i n the end the river triumphs ,for when the mi l l-pond is a marsh no one wil l repai r thedam ; at an unlucky time it wi l l be swept away , and theriver wi l l go on doing its work , a l i ttle behind where itwould have been in the accompl ishment of its task .
We have thus considered the land surface of Worcesteras it i s now , as it w as before the glacial period , and as itwas when the mountains of central Massachusetts togetherwith those of southern New England , had been worn downalmost to sea- level , excepting now and then a single peak .
We have studied the water- courses , noting the facts whichthey demonstrate and the thoughts which they bring tomind . But the subject i s not exhausted ; the wr iting ofthis has brought out many points that need further study
,
and are reserved for the future . But if this paper shal lgive a meaning to the landscape about a s, and shal l l ead us
to think , as we walk or ride out among these bi l ls and overthese brooks and around these ponds , then it has not beenwritten in vain .
