The Sun.
London, England, 1857-04-23 00:00:00

BLECTRO-MAGNETIC ENGINES.

Mr. T. Allan, whose improvements in electric
telegraphs have been recently mentioned, has lat-dy
occasioned consideratde excitement in Paris by the
exhibition, at the desire of the Emperor Napoleon,
of his electro-magnetic engines, which are unques-
tionably the most successful examples in existence
of the application of electro-magnetism as a motive
power. The engines were taken to the Conserva-
toiredes Arts et Metiers on Tuesday, the 14th inst.,
by order of General Morin, the president of the
commission appointed by the Emperor to examine
and report upon them. On Saturday, the 18th,
they were removed to the Tuileries for the inspec-
tion of the Emperor. We are not in apo aloe to
speak definitely of the result of these investigations,
but we have reason to anticipate that the principle
of the engines is about to be tested upon a large
scale ; and we are so well assured of its soundness
that we shall look with confidence for the full suc-
cess of the experiment. The main feAture of Mr.
Allan's invention consists in the application of elec-
tric currents, so as to form several electro-magnets
in succession, by means of which several impel-es
shall be successively given in the same direction
to a rod capable of being moved longitudinally
to any extent which may be required. At the
commencement of a stroke the first of a set of
keepers upon the rod is placed sufficiently near
to the first set of magnets to enable them to
exert an available force upon it, and to move it
through the space that separates them. Therefore,
when a current of electricity is applied to this first
set of magnets, they accordingly draw down the
keeper to them, and move the rod longitudinally
through the space just mentioned. The next
keeper is, by this means, brought within the same
distance from its magnets, and the current of elec-
tricity is at the same moment cut off from the for-
mer audapplied to these, whichthereu ron draw their
keeper to them, and move the rod through an ad-
ditional space or distance equal to the first ; and
the other magnates and their keepers will respec-
tively act in a similar manner in succession, and
thus complete the stroke of the rod ; after which
the opposite side of the rod will be operated upon
similarly, the reciprocating motion thus obtained
bAng converted into rotary motion by means of
the connecting-rod and crank in the ordinary man-
ner. It will be easily seen that the arrangement
of the parts may be readily adapted to all practical
purposes. In fact, nothing could possibly be more
susceptible of convenient adaptation than these
engines, which will work with equal efficiency,
whether the series of magnets be either vertical,
horizontal, or inclined at any angle to suit the dif-
ferent circumstances of manufactures, locomotion
on land, or the propulsion of vessels. Mr. Allan
has also arranged a rotary engine upon analogous
principles, and we have seen it produce very excel-
lent results.—Mechanics' Magazine.

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