7 The 100 Most Influential Inventors of All Time 7

sheet or “can,” the alloy containing small amounts of lead,

cadmium, and mercury. The electrolyte consists of a satu-

rated aqueous solution of ammonium chloride containing

roughly 20 percent zinc chloride. The cathode (positive

terminal) is made of impure manganese dioxide. This

compound is blended with carbon black and electrolyte

to create a damp, active cathode mixture which is formed

around a carbon collector rod, also called an electrode. All

batteries of this type are provided with an overwrap

structure with metal covers for electrical contact.

In 1867 Leclanché gave up his job to devote full time to

his invention; a year later it was adopted by the telegraph

service of Belgium. He subsequently opened a factory to

produce the battery and other electric devices; the busi-

ness was taken over by his brother Maurice upon Georges’s

death in 1882.

Hiram Maxim

(b. Feb. 5, 1840, Sangerville, Maine, U.S.—d. Nov. 24, 1916,

London, Eng.)

H

iram Stevens Maxim was a prolific inventor best

known for the Maxim machine gun.

The eldest son of a farmer who was a locally notable

mechanic, Maxim was apprenticed at 14 to a carriage

maker. Exhibiting an early genius for invention, he

obtained his first patent in 1866, for a hair-curling iron. His

iron was followed by a device for generating illuminating

gas and a locomotive headlight; in 1878 he was hired as

chief engineer of the United States Electric Lighting

Company, the first such company in the United States. In

that post he produced a basic invention, a method of

manufacturing carbon filaments. In 1881 he exhibited an

electric pressure regulator at the Paris Exposition.