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1

The History of Computing:The Early Days

Avi YadgarGala Yadgar

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Outline

Memoryaids

Mechanical calculators

Electro-magnetic

General purpose

Analytical Engine 1834

Relay1835

Harvard Mark I1944

Abacus1300

Sector1598

Napier’s Bones1617

Slide Rule1622

Pascaline1642

Stepped Drum1694

Arithmometer1820

Comptometer1892

Millionaire1899

Difference Engine 1

1821 Difference Engine 21849

Curta1947

Turing Machine1936

Z31941

Differential Analyzer

1921

Harvard Mark II

1949

3

Abacus

• First record: 14th Century, China• “The first computer”• Still used in Asian countries • Uses: add, subtract, multiply, divide

– Fractions and square roots• 1946 Contest:

– Japanese abacus vs. electric calculator

1300

1445The printing press Invented

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Chinese Abacus

9

51+1+1+1

9+7

510+1

1300

http://www.tux.org/~bagleyd/java/AbacusApp.html

(10-3)

9+7=16

51+1+1+1

(-3)

5

Sector

• Thomas Hood, London 1598(Galileo, Padua 1592)

• Problems of the time:– Cannon elevation– Amount of gun powder – Drawing, architecture, surveying

• Proportions

1598

6

Sector

• Principle:

• Problem:

• Solution:

?3

100=

α

X

100

9

27A B

O

A’ B’

O’

α

3100

3'' =⇒= X

ABBA

''''

BAAO

ABOA

=

1598

927100 X

=

2

7

Sector

• The lines:– Arithmetic– Geometric– Stereometric– Polygraphic– Tetragonic– Metallic

1598

8

Napier’s Bones/Rods

• John Napier, Scotland 1617

• Multiplication table disassembled

1617

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Napier’s Bones/Rods

• Uses:– Multiplication– Division– Square roots

1617

46,785,399 x 7 =

10

Logarithms• John Napier, Scotland 1614

(Jobst Burgi, Switzerland) • Principle:

• Logarithmic tables

)log()log(

)log()log(

1010

ba

ba

ba

ba−

+

=

=×⇒

1614

)log()log()log(

)log()log()log(

baba

baba

−=

+=×

11

Slide Rule

• Replaces logarithmic tables• Gunter's Line of Numbers

– Edmund Gunter, England • Slide rule

– William Oughtred, England, 1622• Precision depends on length

1622

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Slide Rule - Operations

• Unary functions:– Reciprocals – Square/Square Root – Cube/Cube Root – Common Logarithms – Sines and Cosines – Tangents and Cotangents

• Binary operations:– Multiplication– Division

1622

3

13

Pascaline

• Blaise Pascal France, 1642

• Wheels turned Manually

• Numbers entered in sequence

• Cumulative sum

1642

htm.pascaline/textes/truc_mat/pages/eveilleau.therese/fr.orange.perso://http 14

• Too complex – Only Pascal could repair

• Expensive– Cost more than replaced people

• Technophobia– Mathematicians feared for jobs

• Decimal– French currency system was not

Pascaline - disadvantages1642

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Stepped Drum

• Design: Gottfried Leibniz, Germany 1694• Produced: Phillip Hann, Germany 1774• Commercial: Charles Xavier Thomas, Philippines 1820

1694

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Arithmometer1820

1829First mainline locomotive

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Arithmometer

• Add by one turn of the handle • Multiply by multiple turns of the handle • Subtract and divide by reversing a switch• Disadvantage: “dialing in the digits”

1820

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Stepped Drum - Curta

• Developed: Curt Herzstark, Buchenwald, 1940’s• Produced: Liechtenstein, 1947• Sold at ~ $120 until 1973

1947

4

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Stepped Drum - Curta1947

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Stepped Drum - Curta

• Simulator: http://www.vcalc.net/curta_simulator_en.htm

1947

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Felt & Tarrant Comptometer

• Dorr E. Felt, 1887• Produced: 1892-1930• Key driven• Fully automatic carries

1887

1876: First long distancephone call

1879: First cash register

1888: Production of automobiles

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Comptometer1887

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Comptometer

• Improved user interface– Fail-safe keys

• Locked the machine if the operator failed to press them completely

– Allow multiple keys to be pressed at once• One per column• Faster adding• Multiplication of some numbers

1887

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Comptometer• “Software”: instructions for figuring

– multiplication– subtractions– division– square root– cube root– interest– exchange– discount* English currency

1887

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25

Millionaire Calculator• Invented: Otto Steiger, 1892• Manufactured: Hans W. Egli, Switzerland 1899• Direct multiplication• Also slower

– Addition– Subtraction– Division

1899

1897First radio station

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Millionaire Multiplication Table1899

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Inside The Millionaire1899

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Back to Tables

• Sources of error: – Calculation– Transcription – Typesetting and printing

• Dionysius Lardner’s Cabinet Cyclopaedia– 40 volumes in 1834, grew up to 134– 3,700 acknowledged errata – How many unacknowledged?

1834

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Difference engine

• Charles Babbage (1791 –1871) – English mathematician, philosopher, mechanical engineer and

(proto-) computer scientist• Calculating polynomials with “repeated differences”

– “Complete complex computation”• Conceived in 1821 • Difference Engine No.2 1847-1849

– Simpler mechanical design

1 20 1 2 1...n n n

n na X a X a X a X a− −−+ + + + +

1821

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Difference Engine

• Calculating polynomials with “repeated differences”

• nth degree polynomials– Starting with the nth difference– Require n registers

• No multiplication• Example:

– Require 2 differences

2( ) 4f x x= +

1849

1878First phonograph

7

6

5

4

3

2

1

2nd diff1st diffF(x)x

5

13

8

20

29

40

3

5

2

2

2

11

9

7

2

2

253

13

6

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Building the engine

• Never built by Babbage– Lack of funding– Insufficient manufacturing technology

Casting: cheap but inaccurate

1849

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Building the engine

• 1853 - First full-scale difference engine• Scheutz (Sweden)• “Tabulating Machine”

– 15-digit numbers– 4th-order differences– Printed output

1853

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Building the engine

• 1985 – 1991: Difference Engine No. 2• The Science Museum in London

– ~4,000 moving parts – 2.6 tons– Built to original designs – Original materials– Accurate repeat parts – 31 figures (103 bits)– 7 differences

1991

343m x 0.7m x 2.5m

1991

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1995

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Analytical Engine

• First General Purpose Machine (1834)– A ‘store’ for holding intermediate results– A ‘mill’ for arithmetic computations– Loops – Conditional branching– Programmable using punched cards

• Borrowed from weaving looms

• Would have required a steam engine – But never been built

1834

7

37

1834

Analytical Engine

Controllerµ

CPU

Punched Tape

Store

Memory I/O Device

I/O Device

I/O Device

I/O DeviceMill

Program Memory

Data Memory

ALU

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Analytical Engine • Ada Lovelace created

programs for the Analytical Engine– Bernoulli numbers

The mill - 1871

1

!2 1n z n

n z dzBi eπ +=

−∫

1834

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Analog Computers

• Physical representation of data– Voltages – Currents– Speed of shafts

1876

40

Differential Analyzer

• The differential analyzer – Invented: 1876, James Thomson– Constructed: 1927, MIT– Solves differential equations by integration– Wheel-and-disc mechanisms perform the integration

1876

1903Wright brother’s first flight

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Differential Analyzer1927

1906Electric washing machine

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Differential Analyzer1927

1929First residential elevator

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43

Analog Computers - Moniac1949

• London, 1949• Water represent money• Tanks represent means of

spending money• Flow represents flow…

– Modeled after financial models

• Surprisingly accurate…

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The Enigma1920

• 1920 to the end of WWII• Electromechanical ciphering machine• Applies polyalphabetic encryption

– State dependant encoding• Mechanical and electrical state

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The Enigma1920

1920’sHousehold refrigerators

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Punched cards

• Used in the textile industry • First adaptation by Babbage

– input and data storage• A competition was held for the US 1890 census

– 1880 US census had taken 7 years to complete• Winner: Herman Hollerith

– Later founded the Tabulating Machine Company– Became IBM

• Used mechanical relays to increment mechanical counters.

• The 1890 census was completed in 6 weeks

1890

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Punched cards

• Specifically-designed layouts • “General purpose“ at 1928• Each IBM-style card had 80

characters– Followed by early terminals– Last two digits for a year

• 30% of the profit of IBM in 1931• Use in machines:

– Sorter– Duplicating Punch– Collator

1928

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Punched Tape

• Based on punched cards– Paper or polyester– Still being sold (1.5m/KB)

9

49

Relays

• Joseph Henry 1835• Electronically controlled electrical switch

– Controlled by an electromagnet – Controls a set of contacts

1835

• With no current the armature and contacts are released• The coil requires low power• The contacts can switch high powers

50

Electromagnetic Relay

• A latching relay – Two relaxed states

(bistable)– a.k.a 'keep' relays

1835

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1848 Logical Gates by Relays

c

b b or c

+V

+Vb c OUT0 0 0 0 1 11 0 11 1 1

bc b or c

0 01

0

1

1848: Boolean algebra

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1941Konrad Zuse's Z3

• 1941 - First programmable fully automatic machine• 2500 relays• Program on punched tape• 5 Hz• 64 22bits words• Floating point• Based on the mechanical Z1

1935First regular TV broadcast

1936: Turingmachine

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Konrad Zuse's Z31941

Z1 – 30,000 moving parts54

Harvard Mark I and Mark II1944

• Built for Harvard by IBM• Mark I - 1944

– Fully automatic – Electromagnetic control– Mechanical counters– 765K components– Hundreds KM of wires– 12m x 2.5m x 0.7m– 4,500kg– Mechanical clock – 72 words– 23 decimal digits words

10

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Harvard Mark I1835

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Harvard Mark I - Front-end1835

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Harvard Mark II1947

• Mark II - 1947– Electromagnetic components– Binary representation– Floating point– Operation specific hardware sµ

sµ

– Complicated programming • 8 instructions

– 125,000 addition– 750,000 multiplication

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Harvard Mark II1947

Harvard Mark II storage

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Bugs

• September 1947 – A moth trapped in a relay

of Mark II

????

• What is the origin of the term “bug”?

• “Bugs” came before computers and computer software– Thomas Edison,1878

“First actual case of bug being found”

“… and it is then that “bugs” – as such little faults and difficulties are called – show themselves…”

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References• Wikipedia, the free encyclopedia

http://www.wikipedia.org/• S.O.S. MATHematics

http://www.sosmath.com/• Online lecture by Michelle Hoyle

http://lecture.eingang.org/index.html

• Online Museum Exhibits:– The ENIAC Museum online

http://www.seas.upenn.edu/~museum/index.html– Computer History Museum, Mountain View, CA

http://www.computerhistory.org/– The Science Museum, London

http://www.sciencemuseum.org.uk/on-line/babbage/index.asp– The Computer Museum, System Source

http://www.syssrc.com/html/museum/– The Museum of HP Calculators

http://www.hpmuseum.org/– John Wolff's Web Museum

http://home.vicnet.net.au/~wolff/calculators/– Stephen Johnston’s web pages

http://www.mhs.ox.ac.uk/staff/saj/arithmometer/