1. COMPUTING DEVICE I (PRE COMPUTER AGE TO 19TH CENTURY)
WEEK THREE
COMPUTING DEVICE I (PRE COMPUTER AGE TO 19TH CENTURY)

2. CONTRIBUTION TO PRESENT DAY COMPUTER
NAME OF DEVICE
ITS FEATURES
BASIC COMPONENT TYPE
CONTRIBUTION TO PRESENT DAY COMPUTER
MAIN USES
Abacus
Beads, strings, could add and subtract on a small scale
Mechanical
Digital counting
For small scale counting and addition
Napier’s bones
Iron rod sliding against each other in a box could multiply and divide on small scale.
Mechanical uses the principle of logarithm
Analog
As calculating machine in small scale businesses and in pre-nursery schools.
Slide rule
Sliding rulers against one another could multiply and divide on small scale.
Used as calculating machine now obsolete
Pascal machine
‘Ratchet carry’ mechanism could add large numbers
Automation
Used as business adding machine now obsolete
Leibnitz machine
Rotating gear system, could multiply and divide large numbers
Used as multiplier to improve on Pascal’s adding machine
Jacquard Loom weaving
It tugged multicoloured threads into patterns by means of array of rods, had holes punched in card warps. Programmed for different patterns using punched cards.
A mechanical textile weaving loom
Binary representation by hole recognition, card-reading technology programming instruction.
Local weaving devices

3. Babbage’s analytical engine
Has the mill, the store, the reader and printer which are prototype of the present processor, memory, input and output devices respectively in present day computer
Electro-mechanical
I/O devices, punched card, memory, processor.
Regarded as the first fully programmable computer.
Hollerith census machine
Could compute large numbers, tabulate and record result
Punched card automation
Used for computing census data and tabulating the result used as one of the early business machine as commercial calculator.
Burroughs machine
Similar to Hollerith’s but could add numbers, record and list result
Listing/sorting concept automation
Used in business as commercial calculator and listing machine

4. ASSIGNMENT List four(4) 19th century computing devices
State two (2) features of Babbage’s and Hollerith machines
State two (2) common features of slide rule and Napier’s bones