An abacus in your pocket

In 1972, market studies indicated that a pocket-sized scientific calculator would go nowhere, but that didn't deter Bill Hewlett and his company, Hewlett-Packard, from developing the Abacus HP-35 handheld calculator. Hewlett wanted to sell a pocket-sized version of its first electronic calculator, the 40-lb 9100A, which HP developed in 1968. The HP-35, as it turned out, was more precise than some mainframe computers. Within months of the calculator's introduction, GE (www.ge.com) ordered 20,000 units, according to The Museum of HP Calculators (www.hpmuseum.org). When someone discovered a bug after HP had shipped 25,000 units, the company offered free replacements.

The rest is history. HP scientific calculators are standard fare today—with everyone from high-school math students to seismologists. Electrical Engineer David Hicks founded the Museum of HP Calculators, which claims no affiliation with HP. Hicks is only one of many calculator collectors who worship the older HP, Sharp, and TI scientific calculators, some of which you can read about at the Datamath Calculator Museum (www.datamath.org). TI introduced the SR-50 electronic slide rule in 1973 at less than half the HP-35's price.