Authentic Science Fiction Monthly, No. 56 — page 64: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

AUTHENTIC SCIENCE FICTION demonstrated which “reads” information, not from coded media, but from a printed page, using a specially de- signed type. Another device, not developed particularly for use with calculating machines, produces a convenient system | of electrical signals from speech directed into a micro- phone. These bricf examples indicate that the input system could be made very flexible. Numerous methods of in- formation storage are used, including the familiar magnetic tape recording. Theoretically, the storage capacity of these machines is unlimited, al- though in practice economic factors naturally set a limit to the size of the “‘memory.”’ The arithmetical unit, apart from its simple facilities for com- _parison, normally includes facilities for addition and subtraction, and occasionally ~ multiplication, but rarely for other mathematical opera- tions. This may, ai first sight, appear torestrict the machine’s capabilities, but it can be shown that the majority of mathematical operations are able to be carried out by a series of operations involving only addition and subtraction (for example, multiplication can Obviously be effected by a 63 series of additions, and divi- sion byaseries of subtractions). The number of steps in a problem is then greatly in- creased, but the speed of operation of the machine outweighs this disadvantage. For instance, in some of the faster machines, two large numbers can be added to- gether in less than two thous- — andths of a second, and multiplied in less than three thousandths. It should not, however, be imagined that speed alone is the determining factor in a machine’s eff- ciency; other factors, too involved for discussion here, may be more important than speed. THE RESULTS The calculations having been completed, the results are then translated by the output into the form required by the user. For most cases, the results will be printed, by teleprinter devices, but other methods can be used, such as the controlling of machine tools or industriai and chemical plant processes. Special purpose computors are already widely used for applications such as aircraft control (automatic pilot), for aiming of guns and search- comiclooks.corn