Description of a Relay Calculator

Cambridge, Massachusetts: Harvard University Press, 1949. First Edition. Cloth. Near Fine/Fair. First Edition. xvi, [2], 336 pages. 4to [10 3/4 x 8 3/8 inches]. Publisher's blue cloth. The rare dust jacket is present, albeit chipped, stained, and worn (especially at foredges). Bright and clean internally. Cloth. "The electromechanical Harvard Mark I was the first programmable calculating machine to actually produce mathematical tables, fulfilling the dream of Charles Babbage originally set out in print in 1822." (OOC, #411)

"The manual for the Harvard Mark II, a relay-based calculator built for the navy during the last year of World War II. (truncated) It was installed at the Naval Proving Ground in Dahlgren, Virginia, in 1948, where it was used mainly for the development of ballistics tables. The Mark II's design did not depart radically from that of its predecessor in that it employed electromechanical equipment and was programmed via paper tapes, 'but otherwise it was very different. Where the Mark I used rotary mechanical systems (with magnetic clutches) for storing numbers, the Mark II used relays. The way of programming it was very different (i.e. the instruction set was different). The fact that it was essentially two machines which could be combined for large jobs or have each half running independent jobs was quite different.' (MRW Other innovations included a floating decimal point and a new type of relay. It was considerably faster than the Mark I ... The Manual for the Harvard Mark II calculator was written primarily by Grace Hopper, assisted by Constance K. Rawson, Peter O. Cioffi and Richard D. Woltman. It was completed by Charles H. Richards and K. B. Mitchell" (OOC)

Volume XXIV of the Annals of the Computation Laboratory of Harvard University. All volumes in the series were heavily used, and finding copies in dust jacket is getting difficult.

Literature:
Hook and Norman, Origins of Cyberspace, #416, 411 (referring to Mark I). (Inventory #: 29129)