Lesson Notes By Weeks and Term - Senior Secondary School 1

SUBJECT: ICT

CLASS:  SS 1

DATE:

TERM: 1st TERM

 
WEEK FOUR

TOPIC: COMPUTING DEVICES 1(Pre- computer age to 19 century)

Reference book: Hiit @ School, Computer Studies for Senior Secondary Education.

CONTENT

NAPIER’S BONE

The need for a better calculating device was felt as time passed.  In 1617 an eccentric Scotsman named John Napier a mathematician invented logarithms, a technology that allows multiplication to be performed through addition. The magic ingredient is the logarithm of each operand, which was originally obtained from a printed table. But Napier also invented an alternative to tables, where the logarithm values were carved on ivory sticks which are now called Napier’s bones.  The device is made up of a set of eleven rods, with four sides each which was used as a multiplication tool.  These rods were made from bones and this was the reason why they were called Napier Bones.  The rods had numbers marked in such a way that, by placing them side by side, products and quotients of large numbers can be obtained.

PASCALINE

In 1642 Blaise Pascal, at age 19, invented the Pascaline as an aid for his father who was a tax collector. He was a French mathematician. Pascal built 50 of this gear-driven one- function calculator which could only add. The odometer portion of a car’s speedometer used the very same mechanism as the Pascaline to increment to the next wheel after each full revolution of the prior wheel. At the age of 12, he was discovered doing his version of Euclid’s thirty-second proposition on the kitchen floor. He went on to invent probability theory, the hydraulic press, and the syringe. Numbers were entered by dialing a series of numbered wheels in this machine.  A sequence of wheels transferred the movements to a dial, which showed the result.  Though addition and subtraction were performed the normal way, the device could perform division by repeated subtraction and multiplication by repeated addition.

LEIBNITZ CALCULATING MACHINE

A few years after Pascal, 1694, a German; Gottfried Wilhelm Leibnitz (co-inventor with Newton of Calculus) managed to build a four-function (addition, subtraction, multiplication and division) calculator that he called the stepped reckoner. This calculator instead of gears employed fluted drums having ten flutes arranged around their circumference in a stair-step fashion. Although the stepped reckoner employed the decimal number system (each drum had 10 flutes), Leibnitz was the first to advocate the use of the binary number system which is fundamental to the operation of modern computers. He was considered one of the greatest philosophers but he died poor and alone.  The machine is still being used.

EVALUATION

Discuss briefly components and features of two computing devices mentioned above.

READING ASSIGNMENT: HiiT @ School, Computer Studies for Senior Secondary Education. Chapter Three, pages 6-7.

WEEKEND ASSIGNMENT

OBJECTIVES

1. Napier device is made up of how many rods? a) 11 b) 4 c) 15
2. Who was considered as one of the greatest philosophers?  a) Pascal b) Leibnitz c) Abacus
3. Who advocated the use of binary system in computing? a) Pascal b) Leibnitz c) Napier
4. What age was Pascal when he invented Pascaline? a) 19 b) 12 c) 21
5. Who invented the probability theory? a) Pascal b) Leibnitz c) Napier

THEORY

Write short note on the following: Pascaline, Napier’s bone and Leibnitz calculating machine.