Scientific American Supplement, No. 664, September 22,1888Various
History
Scientific American Supplement, No. 664, September 22,1888
Various
Science -- Periodicals
At the recent meeting of the Institution of Mechanical Engineers,
Dublin, Mr. Davey, of Leeds, spoke of synchronizing mechanisms. He had
occupied some of his spare time in attempting to synchronize clocks
from a standard clock. The problem is similar to the present one,
except that it is rough-and-ready, compared to the present one. He had
a novel electrical pendulum, to drive a seconds pendulum by
electricity. Electrical clocks are notoriously bad timekeepers; on
account of variation in the strength of the electrical current, the
battery falls off. He had constructed an electric clock having a
seconds pendulum, and recording an impulse once a minute. On the
pendulum he had a little ratchet wheel, R, having thirty teeth. The
pawl was connected with a lever, M, fixed at the top. On the face of
the wheel a little pin rotates with the wheel. On the side of the
clock case was a contact maker, which closed the circuit by the pin on
the ratchet wheel, R, once every minute. The weight was lifted by the
electric current, and by its fall gave an impulse to the pendulum. The
pendulum was a free swinging pendulum for 59 sec., and the increase of
the arc could scarcely be detected.
* * * * *
COAL TAR AS FUEL FOR STEAM BOILERS.
By JOHN McCRAE, of Dundee.
About three years ago, when the sudden and serious fall took place in
the value of the secondary products produced in gas works, many gas
managers--ever desirous of doing their very best for their
employers--were forced to look around for some better market in which
to dispose of the products which had so seriously fallen in value.
This was no easy task; and even now it forms very uphill work indeed.
A comparatively new market has been created for the disposal of boiled
tar at several of the German ports. But the expense and difficulty of
loading ships with tar in casks take very much from the saving derived
from the new manner of disposal. It occurred to me, therefore, that we
must look nearer home for a remedy.
Public-domain text, read in full here on John Shaqi.
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