Page:Alan Turing - Proposed Electronic Calculator (1945).pdf/20

 Space for LC and CA. This is difficult to estimate, but 5 eight foot racks might be a reasonable guess and would require another 200 square feet or more. In the same room we would put the input and output organs which might occupy 40 square feet. We should also provide another 100 square feet for operators tables, etc. 400 square feet would not be unreasonable for this room.

Card storage room. We would probably keep a stock of about 100,000 cards, a very insignificant number by normal Hollerith standards. 200 square feet would be quite adequate.

Maintenance workshop. We would do well to be liberal here. 400 square feet.

This total of 1400 square feet does not allow for the planning of operations, which would probably be done in an office building elsewhere, nor for the processing of Hollerith cards which will probably be done on machinery already available to us.

Cost. It appears that the cost of the equipment will not be very great. An estimate of £20 per delay line would be liberal, so that 200 of these would cost us £4000. The value equipment at £5 per inch of rack space might total £5000. The power supply might cost £200. The Hollerith equipment would be hired, which would be advantageous because of the danger of it going out of date. The capital cost of such Hollerith equipment even if bought would not exceed £2000. With this included the total is £11,200.

 Part II./