The morning call., 1891-09-13
WORLDS FAIR NOTES.
A Powerful MiCrOSc0De-A Marvellous Clock
The Machinery Annex.

magnificent microscope has just been
completed by the Munich POeller Physical
and Optical Institute for the great Chicago
Exposition, at a cost of $3.50. 1t possesses
a magnifying power of II, coo diameters. AS
might be expected, electricity plays an i'm
portant part in the working Of this gigantic
instrument, which, after inspection by
American citizens, is expected to give an
impetus to the Munich mart for scientific
apparatus. The electricity furnishes and
regulates the source of light, which placed
in the focus of a parabolc aluminium re-
fiector reaches an intensity of 1900 can
die power. The electricity also provides
the means Of an ingenious automatic
mechanism for the centering of the
quadruple condensers and Illuminating the
lenses. There is an arrangement for the
exact control of the distance of the carbon
point The most important novel feature
is the cooling machine, which is indispen-
sable on account of the extreme heat, 1-43
calorieS per second, generated by the intense
Illuminating arrangement. a machine regu-
lated by HelmhOtZ electric centrifugal
regulator provides the several microscopic
and pOlarisCopic systems of the apparatus
with a fine spray of fluid carbOnie acid,
which Immediately after its release from the
copper vessel, in witch 1t is held under a
pressure of % atmoSpheres, becomes con-
verted into gaseous matter, so intensely
cold that only .O0OO7 gramme of carbouc
acid per second is required 10 give the re-
suit. The magnTyIng power of the appa-
ratus with ordinary 0bjectiveS, as has been
stated. is about 11,000 diameters, but with
the oil immersion il can be increased to 16, COO.
genius at Muhlenberg, Pa, has COM
pleted marvellous clock for exhibition at
the fair Around the dial is railway
track, on which a miniature locomotive
makes the round every five minutes. 1t
REQUIRES magnifying glass to see the deli
cate machinery. The oil-cups at the jour
mails are so small that nothing larger than a
hair can be inserted. There is a headlight
ana bell tlag-nOldeTs on the pilot, whistle
and everything connected with Il locomotive.
It has link motion under the enEine TO
reverse it. The weight of the locomotive is
one and half pounds, and it has been
named 1.-The Gem"
1t has been decided to have the ma
chineTy annex an annex in TACT instead
Of being an isolated structure as at first
planned. The annex Will adjoin Machinery
Hail on the west. The entire structure will
thus measure 5O0X1400 feet and be second in
size only to the Manufactures Building,
the dimensions of which are 7SSXl6SS feet.
With its galleries, the latter building will
have forty acres of floor space.
The suggestion made by prominent men,
bers Of the National Society OF the Sons of
the American Revolution and of the
Sons of the Revolution. that October
11th should be celebrated throughout the
world as the Fourth OF July is celebrated in
the United States, is meeting with general
approval.
The first cotton gin, made by Eli Whitney,
will be exhibited at the exposition 6Y the
New Orleans Machinery Company, which
will also make an extensive exhibit of cot
ton gins, sugar mills and other machinery.
Harry B. Worthington has offered TO fur
nish the exposition. free of charge, pumps
with capacity Of 100000 gallons Of water
a day.
Among the exhibits from Southern Cali
fOInia will be a model constructed to illus
trate irrigation. A committee has already
been chosen to prepare ii.
Siam has decided to make an exhibit at
Chicago which shall eclipse the one it made
at the Paris exposition, where it carried off
the hOnOrs of the Oriental section.
Michigan will construct its building
wholly Of Michigan material, and will send
it to Chicago in sections.