was made to spring up ten inches through the
air, and says that he can as readily move a bar weighing a hundred tons
through a space of a hundred feet. He expects to be able to apply it to
forge hammers, pile drivers, &c, and to engines with a stroke of six,
ten, or twenty feet. He exhibited also an engine of between four and
five horse power, worked by a battery contained in a space of three
cubic feet. It was a reciprocating engine of two feet stroke, the engine
and battery weighing about one ton, and driving a circular saw ten
inches in diameter, sawing boards an inch and a quarter thick, making
eighty strokes a minute. The professor says that the cost of the power
is less than steam under most conditions, though not so low as the
cheapest steam engines. The consumption of three pounds of zinc per day
produces one horse power. The larger his engines the greater the
economy. Some practical difficulties remain to be overcome in the
application of the power to practical purposes on a larger scale: but
little doubt seems to be entertained that such an application is
feasible. The result is one of very great importance to science, as well
as to the arts of practical life.--We made a statement in our July
number of the pretensions of Mr. Henry M. Paine, of Worcester, Mass., to
having discovered a new method of procuring hydrogen from water, and
rendering it capable of giving a brilliant light, with great case and at
a barely nominal expense, by passing it through cold spirits of
turpentine. His claims have been very generally discredited, and were
supposed to have been completely exploded by the examinations of several
scientific gentlemen of Boston and New York. Mr. GEORGE MATHIOT, an
electro-metallurgist attached to the United States Coast Survey, and a
gentleman of scientific habits and attainments, has published in the
Scientific American, a statement that he has succeeded in a kindred
attempt. He produced a very brilliant light, nearly equal to the
Drummond, by passing hydrogen through turpentine: and in thus passing
the gas from thirty-three ounces of zinc through it, the quantity of
turpentine was not perceptibly diminished. "In this case," he says, "the
hydrogen could not have been changed into carburetted hydrogen, for coal
gas contains from four to five times as much carbon as hydrogen, and
pure carburetted hydrogen has six times as much carbon as hydrogen; and,
as 33 ounces of zinc, by solution, liberate one ounce