7 Wilhelm Conrad Röntgen 7

Thomas Alva Edison demonstrating
his tinfoil phonograph, photograph
by Mathew Brady, 1878. Courtesy
of the Edison National Historical
Site, West Orange, N.J.

Röntgen’s discovery of X-rays was met with worldwide
scientifi c and popular excitement. Within months of the
discovery there was extensive literature on the subject: a
British surgeon had localized a bullet in a boy’s wrist before
operating; stones in the urinary bladder and gallbladder
had been demonstrated; and fractures had been displayed.
Along with the discoveries of radioactivity (1896) and the
electron (1897), the discovery of X-rays ushered in the study
of the atomic world and the era of modern physics.

Thomas Edison

(b. Feb. 11, 1847, Milan, Ohio,

U.S.—d. Oct. 18, 1931, West

Orange, N.J.)

T

homas Alva Edison

was an American

inventor who, singly or

jointly, held a world

record 1,093 U.S. patents.

In addition, he created

the world’s fi rst industrial

research laboratory.

Edison was the

quintessential American

inventor in the era of

Yankee ingenuity. He

began his career in 1863,

in the adolescence of the

telegraph industry, when

virtually the only source

of electricity was primi-

tive batteries putting out

a low-voltage current.