Evening star. [volume] (Washington, D.C.) 1854-1972, 1889-03-22
MICROSCOPES.
How to Select One-The Wide Variety
I'm Styles and Prices.
From the New York Evening Post.

From the New York Evening Post.
For what price can you buy a microscope
repeated Fulton street optician 10 a reporter
of the EueniRg Post We'll. that depends upon
what kind of one You want. I can sell you Q
simple instrument which. with its three lenses
combined has a power of thirty-three diane
tiers, for $3.50. With il you can see many Of
the larger animalcule in pond water, the scales
from butterfy's wing, pollen-grains from
plants, and thousands of other objects not wis.,
BILE to the naked eve. From 1850 the prices
for microscopes range up 20 $3.50 aud 600.
Now let me tell you something about the differ
ent styles and grades. SO that il you ever want
10 buy one, You will know what 60 get. Ia the
hrst place. very common mistake made by
persons attempting to select & microscope Is 20
Judge OF the excellence of an instrument by the
amount OF It's magRiiying power. No object
should be viewed with a power greater than
that required TO show its structure aud il that
can be done with thirty diameters il is, TO saw
the least, unnecessary Ia use one hundred. This
Is especially the case with low-priced instru-
ments. where the apertures Of the detectives
are small and the connections not 40 exact as in
the higher grades. rendering them more liable
to give false impressions of objects. Moreover.
II Is absolutely impossible 10 view opaque OBJ
jects satisfactorily by the reflected light of cheap
compound microscopes. For those who wish
TO dissect flowers and insects for examination
simple instrument Is better
In selecting a microscope the essential
points to he observed are that the lenses show
objects clear and well-defned that the stand
be of good material and workmanship. and
that there be no lateral movement IN the adj
justments of the focus Further. that the
focus be instantly changeabie when desired.
and that II have joint for inclination. Now
for the different kinds of microscopes. The
simplest, of course. Is the single glass such as
l. kar nd one nd fba
common pocket glass with from one TO three
lenses. The simplest microscope. with a stand.
Is the one L mentioned for $3.50. As ! said,
with its three lenses combined il has a magni-
tying power of 33 diameters. IL packs in box
that acts as base for the upright brass stem.
With IT comes animalcule cage a pair of
brass forceps. watch-glass. two PLAIN glass
slips. and a prepared object. The school micro
scope Is SIMILAR, but works easier. and is better
adapted for school purposes. OF the compound
microscopes. here Is one selling for g. so which
is the simplest. Ii is of polished brass. as you
see, with one piece and one object-glass, mag
nifying when combined about 40 diameters. or
LOCO times, the power being calculated dby
squaring the diameter
This powerful instrument for household use
with Its two object-glasses. magnifies from 800
TO lO.OoO times. and ranges in price according
TO size and quality from IS to Sl2. For ordi-
nary use, an amateur microscopic can buy an
instrument for from S23 TO go which will
answer his every purpose. Such microscope
will have stage with adjustable spring clips. a
revolving diaphragm with four apertures be-
meath the stage. and a concave rejecting mir
ror for use under or above the stage. Ii can
magnify 27.00O times. and with the addition of
one-fifth object-glass. this can be increased TO
$4,000 times. For students in histology and
vegetable anatomy we have instruments that
range in price from $50 TO 500. and when one
of the cheapest is furnished with condenser
polariscope, camera lucida. spot lens, zoophyte
trough. live box. and forceps it is complete for
almost any investigation