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I have a book somewhere in the basement on organising calculations from the early twentieth century, back when computer was a job title and job runtime was measured in weeks...

===Update===

Couldn't find the one I was looking for, but I did dig up Eckert, Punched Card Methods in Scientific Computation (1940).

From Chapter VII "The Multiplication of Series":

p.68 "By a continuation of this process we obtain about 100 groups of cards each with its rate card. Since the capacity of the multiplier is eight digits, those groups which have 9 and 10 digit multipliers and eight digit multiplicand are done in two groups. The few terms with large multiplier and multiplicand are done by hand. In a series with reasonable convergence there may be about 20,000 cards altogether. The reproducer is of course used to check the punching."

10 decimal digits is what, 33 bits?

p.74 "The machine time for 100 series is as follows:

    Original punching and verifying . . . . 2   days
    Listing and summary punching checksums. 1/4 day
    Sorting and gang punching duplicates. . 1   day
    Multiplying . . . . . . . . . . . . . . 1   day
    Sorting, tabulating, and summary punch. 1   day
In this example the checks would have been exact had we included a card for each product regardless of size, but this would have required about forty thousand cards instead of four or five thousand, and the multiplying time would have been over a week instead of one day."

I guess in principle a punched card could have contained 80 decimal places, but it seemed like the ALU equivalents were much narrower.

(this was published by the Thomas J. Watson Astronomical Computing Bureau)




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