rtrush to Bushmills, at the Giant's Causeway, engaged his
attention; and this, the first work of its kind in the United Kingdom,
and to all appearance the pioneer of many similar lines, was one of his
very last undertakings.

In the recent development of electric lighting, William Siemens, whose
fame had been steadily growing, was a recognised leader, although
he himself made no great discoveries therein. As a public man and
a manufacturer of great resources his influence in assisting the
introduction of the light has been immense. The number of Siemens
machines and Siemens electric lamps, together with measuring instruments
such as the Siemens electro-dynamometer, which has been supplied to
different parts of the world by the firm of which he was the head, is
very considerable, and probably exceeds that of any other manufacturer,
at least in this country.

Employing a staff of skilful assistants to develop many of his
ideas, Dr. Siemens was able to produce a great variety of electrical
instruments for measuring and other auxiliary purposes, all of which
bear the name of his firm, and have proved exceedingly useful in a
practical sense.

Among the most interesting of Siemens's investigations were his
experiments on the influence of the electric light in promoting
the growth of plants, carried out during the winter of 1880 in the
greenhouses of Sherwood. These experiments showed that plants do not
require a period of rest, but continue to grow if light and other
necessaries are supplied to them. Siemens enhanced the daylight, and, as
it were, prolonged it through the night by means of arc lamps, with the
result of forcing excellent fruit and flowers to their maturity before
the natural time in this climate.

While Siemens was testing the chemical and life-promoting influence of
the electric arc light, he was also occupied in trying its temperature
and heating power with an 'electric furnace,' consisting of a plumbago
crucible having two carbon electrodes entering it in such a manner that
the voltaic arc could be produced within it. He succeeded in fusing
a variety of refractory metals in a comparatively short time: thus, a
pound of broken files was melted in a cold crucible in thirteen minutes,
a result which is not surprising when we consider that the temperature
of the voltaic arc, as measured by Siemens and Rosetti, is between
2,000 and 3,000 Deg. Centigrade, or about one-third that of the probable
temperature of