discovery of importance, and
naturally follows from Faraday's far greater and more original discovery
of magneto-electric generation.

In 1874, Dr. Siemens published a treatise on the laying and testing of
submarine cables. In 1875, 1876 and 1877, he investigated the action of
light on crystalline selenium, and in 1878 he studied the action of the
telephone.

The recent work of Dr. Siemens has been to improve the pneumatic
railway, railway signalling, electric lamps, dynamos, electro-plating
and electric railways. The electric railway at Berlin in 1880, and Paris
in 1881, was the beginning of electric locomotion, a subject of great
importance and destined in all probability, to very wide extension in
the immediate future. Dr. Siemens has received many honours from learned
societies at home and abroad; and a title equivalent to knighthood from
the German Government.

VI. LATIMER CLARK.

MR. Clark was born at Great Marlow in 1822, and probably acquired his
scientific bent while engaged at a manufacturing chemist's business
in Dublin. On the outbreak of the railway mania in 1845 he took to
surveying, and through his brother, Mr. Edwin Clark, became assistant
engineer to the late Robert Stephenson on the Britannia Bridge. While
thus employed, he made the acquaintance of Mr. Ricardo, founder of the
Electric Telegraph Company, and joined that Company as an engineer in
1850. He rose to be chief engineer in 1854, and held the post till 1861,
when he entered into a partnership with Mr. Charles T. Bright. Prior to
this, he had made several original researches; in 1853, he found that
the retardation of current on insulated wires was independent of the
strength of current, and his experiments formed the subject of a Friday
evening lecture by Faraday at the Royal Institution--a sufficient mark
of their importance.

In 1854 he introduced the pneumatic dispatch into London, and, in 1856,
he patented his well-known double-cup insulator. In 1858, he and Mr.
Bright produced the material known as 'Clark's Compound,' which is so
valuable for protecting submarine cables from rusting in the sea-water.
In 1859, Mr. Clark was appointed engineer to the Atlantic Telegraph
Company which tried to lay an Anglo-American cable in 1865. in
partnership with Sir C. T. Bright, who had taken part in the first
Atlantic cable expedition, Mr. Clark laid a cable for the Indian
Government in the Red Sea, in order to establish a telegraph to India.