the sun. Sir Humphry Davy was the first to observe the
extraordinary fusing power of the voltaic arc, but Siemens first applied
it to a practical purpose in his electric furnace.

Always ready to turn his inventive genius in any direction, the
introduction of the electric light, which had given an impetus to
improvement in the methods of utilising gas, led him to design a
regenerative gas lamp, which is now employed on a small scale in this
country, either for street lighting or in class-rooms and public
halls. In this burner, as in the regenerative furnace, the products
of combustion are made to warm up the air and gas which go to feed the
flame, and the effect is a full and brilliant light with some economy of
fuel. The use of coal-gas for heating purposes was another subject which
he took up with characteristic earnestness, and he advocated for a time
the use of gas stoves and fires in preference to those which burn coal,
not only on account of their cleanliness and convenience, but on the
score of preventing fogs in great cities, by checking the discharge
of smoke into the atmosphere. He designed a regenerative gas and coke
fireplace, in which the ingoing air was warmed by heat conducted from
the back part of the grate; and by practical trials in his own office,
calculated the economy of the system. The interest in this question,
however, died away after the close of the Smoke Abatement Exhibition;
and the experiments of Mr. Aiken, of Edinburgh, showed how futile was
the hope that gas fires would prevent fogs altogether. They might indeed
ameliorate the noxious character of a fog by checking the discharge
of soot into the atmosphere; but Mr. Aiken's experiments showed that
particles of gas were in themselves capable of condensing the moisture
of the air upon them. The great scheme of Siemens for making London a
smokeless city, by manufacturing gas at the coal-pit and leading it in
pipes from street to street, would not have rendered it altogether a
fogless one, though the coke and gas fires would certainly have reduced
the quantity of soot launched into the air. Siemens's scheme was
rejected by a Committee of the House of Lords on the somewhat mistaken
ground that if the plan were as profitable as Siemens supposed, it would
have been put in practice long ago by private enterprise.

From the problem of heating a room, the mind of Siemens also passed to
the maintenance of solar fires, and occupied itself with the sup