Men and Machines before Babbage

The calculator is generally thought of as the brainchild of Charles Babbage, who produced his Difference Engine and designed his Analytical Engine some 150 years ago. In fact, however, Babbage stood on the shoulders of men before him who earlier saw the necessity for counting tools. Three men, in particular, had built operating calculators more than a century before Babbage built his.

The first real calculating machine was produced in 1647 by Blaise Pascal, a man of astonishing breadth of vision even for those days of nonspecialization.

About the size of a cigar box, the Arithmetic Engine used wheels and a stylus (иголка, перо) to perform its operations. The principle was identical with that used in today's taximeter: digits from 0 to 9 were arranged on wheels, and turning one wheel a full revolution (оборот) caused its neighbour (сосед) to be advanced one notch (зубец). By adjustment of the metal strip at the top, the machine can be made to perform either addition or subtraction.

Eight Pascals are known to exist. Four are in the Musee du Conservatoire Nationale des Arts et Metiers in Paris; one at Dresden; one at Clermont-Ferrand; one in the Leon Parce collection; and one in the IBM collection.

Morland's multiplying calculator

The second mechanical calculator known to us was produced by Samuel Morland about 20 years after Pascal's, which had been pressed into tax (налог) service in France. Morland's first device was also intended for adding and subtracting currency this time English currency.

He constructed an adding and subtracting machine with gear wheels (зубчатые колеса) operated by a stylus. Addition was performed by turning wheels clockwise, subtraction by the reverse. Only four inches by three

inches and less than a quarter of an inch thick, this was in some ways the forerunner of the pocket calculator. The carrying was not automatic, however, for the operator had to remember to add the extra digits indicated on the auxiliary dials (шкала, диск).

Leibniz's calculating machine

Gottfried Wilhelm Leibniz, born in Leipzig in 1646, was by far the greatest scientific genius of his day. And as might be expected, his calculating device was far superior to any other built to that time.

A half century after Pascal developed arithmetic machines, Leibniz took the next great step forward. His was the first to multiply and divide directly, as well as to subtract directly without resorting (обращаться) to complement arithmetic.

The Leibniz calculator consisted of a series of stepped cylinders, each carrying nine teeth of varying lengths. Smaller gears were set above them, each representing a digit of the multiplicand (множимое) and placed so as to be engaged (зацеплять) by that number of the long gear's teeth. Each complete turn of the set of long gears registered the multiplicand once; the multiplier (множитель) was expressed by the number of times the long gears were turned.

Although there were minor flaws (недостаток) in the design and perhaps technical problems in construction, Leibniz's invention was based on important principles, many of which were to be used in later mechanical calculators. These innovations (новшество) included the principle of simultaneous (одновременный) entry of all digits in a multiple-digit number, entry of numbers into the accumulator from a movable carriage (каретка), the stepped cylinder, delayed and sequential carry, the cycle counter, and reversible rotation.

One machine was built about 1694 and now is preserved in the Library in Hanover, West Germany, another machine, built in 1704, had disappeared.

На основании прочитанных текстов из истории вычислительной техники заполните следующую таблицу:

Name	Time	Event	Basic parts	Functions
Pascal	in 1647	the Arithmetic Engine	wheels and stylus	addition, subtraction
…	…	…	…	…

VII. Пользуясь этой таблицей, расскажите об истории развития ЭВМ.

Поколение (годы)	Элементная база		Отличительные черты
	Переключательные элементы	Элементы памяти	Аппаратные средства	Программные средства
Первое поколение (1945-1954)	Вакуумные лампы	Ртутные линии задержки, ЭАТ	Операционный блок с фиксированной запятой	Машинный язык, язык ассемблера
Второе поколение (1955-1964)	Транзисторы	Память на магнитных сердечниках, магнитные диски	Операционный блок с плавающей запятой	Языки высокого уровня, библиотеки подпрограмм
Третье поколение (1965-1974)	ИС (МИС, СИС)	ИС памяти	Микропрограммное управление, конвейерная обработка, кэш-память, миникомпьютеры, микропроцессоры	Мультипрограммирование, операционная система, виртуальная память
Третье с половиной поколение (1975-1984)	БИС	БИС памяти	Мультиплексный конвейер, встроенный матричный процессор, суперкомпьютер, многопроцессорные системы, персональные компьютеры, рабочие станции	Многосегментная виртуальная память, виртуальные машины, языки искусственного интеллекта
Четвертое поколение (1975-1984)	СБИС	СБИС памяти	Компьютерные сети, разделение рабочих станций по назначению	Виртуальная аппаратура, распределенные ОС, сетевая архитектура, экспертные системы

Unit 3

I. Запомните следующие слова.

a batch пакет, партия, группа

off-line автономный

on-line управляемый

an order порядок

a job задание; работа

timesharing разделение времени

time-slice временной интервал (квант)

arrangement размещение; расположение

request запрос; требование

advantage преимущество; достоинство

disadvantage недостаток

again снова: опять; кроме того

also также; к тому же

namely именно; то есть

II. Найдите в словаре значения следующих глаголов. Глаголы выучите.

to schedule, to divide, to link, to appear, to solve, to allow, to be responsible for

III. Прочитайте и переведите следующие словосочетания.

some какой-то; несколько

the same тот же самый; такой же

some number of bits, the same number of bits, some pattern of bits, the same pattern of bits, the same complex pattern of bits, some set of instructions, the same set of instructions, the same set of instruction codes, machine language program, some machine language programs, the same machine language programs, low-level language, high-level language, batch

processing, remote batch processing, card reader, computer operator's office, to move data to memory, to hold data in memory, memory locations

IV. Переведите предложения на русский язык, обращая внимание на слово involved.

Страдательное причастие от глагола to involve переводится: данный, о котором идет речь, затронутый, рассматриваемый, если это причастие стоит после определяемого существительного.

1. The magnitude for all of these quantities involve the question of standard states.

2. The design of reliable apparatus for this purpose involves a number of difficulties.

3. The Fisher method involves certain losses.

4. Every field of chemistry involves different chemical reactions.

5. The exact representation of information depends on the characteristics of the particular system unit involved.

6. The word "micro'' is used to indicate the small physical size of the components involved.

7. The numeric execution unit executes all instructions that involve the register stack.

8. The explanation of much of the physical phenomena involved presents some difficulties.

I. Прочитайте следующий текст.

Читая текст, Вы встретитесь с повелительным наклонением, которое выражает совет, побуждение к действию, просьбу, приказание. Когда просьба или приказание обращены ко 2-му лицу ед. и мн. числа, форма повелительного наклонения совпадает с формой инфинитива без частицы to. Например: Define the value of angle. Be careful. Определите значение угла. Будьте внимательны.