The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1884-08-16
TIE MICROSCOPE.
its uses and Revelations.


more liberal in contributing of their knowledge
to the general information, through the press.
Believing your criticism just, at least to some
extent, and no one else having responded, have
concluded with your consent, to contribute an
occasional chapter to 1.-THE Microscope, Its Uses
and Revelations" if find they are appreciated.
/ do not write these articles for the advanced
scientific student but for those who have the
spirit Of observation, and who desire to know
something of the unseen world lying every where
about us For years have had the use of
microscope, and, by giving odd moments and
leisure hours, of evenings, to its USE have be-
come acquainted with many hundreds of the
minute forms of life about us, and many other
facts in histology, biology and kindred sciences,
without, in any degree trespassing upon time
that belonged to my other business. Others
may surely do as we'll Many hours given to
idleness and loafng might be we'll improved in
this way The observations recorded in these
articles shall be chiefly my own, drawn from ex-
perience, not from reading.
The microscope is, as its name implies, an in
strument for making visible small things. 1t
may be either simple or compound. A simple
microscope is composed of one or more lenses in
a single combination and is usually adapted to
examining comparatively large objects only
A compound microscope is composed of two OF
more lenses arranged in two more systems
and generally consists of an objective, the tense
nearest to the object, and an eye-piece-the
| lens nearest the eye, and an intervening tube
The eyepiece magniies the image formed by the
objective. Microscopes vary greatly in their de-
gree of excellence. An instrument that will
give fair satisfaction and do ordinary work, can
variety of work, give much pleasure and be
very useful in affording information, may be
had for $50 to $lO0. OF course, the best in
struments cost more than these figures One
who is not acquainted with microscopes, will al
ways do we'll, in making selection, to get the
assistance of some one who has experience. The
magnifying power of microscope depends upon
the objective, eye-plece and len 9Th OF tube. Eye
pieces and detectives are movable and we use
as many different combinations Of them as we
may desire, on the same stand thus varying
the power at pleasure For example, if the
tube of our microscope be ten inches long, and
our objective have focal distance of one inch,
we have magHifying power of ten diameterS,
equal to 100 area if we now put into
the upper end of the tube an eye-piece of one
inch focal distance, we shall magnify the image
iect, with this combination, will be magnifed
ten times ten diametefs, or 100, equal to 10000
area. If we eye-pieee of ehalf inch
focus we shall have 20 by To- or 200 diameters;
or if we use half-inch objective and one-inch
eyepiece, we have the same result. In speaking
of the magnifying power of a microscope, we
usually have reference to diameter and not area.
To find the area, square the diameter,
A third lens is sometimes used between the OBJ
jectiye and ye-pece, called an amplifer which
magnifes the image formed by the objective
before it reaches the eye-piece. By using OBJ
jectives and eye-pieces of different powers, and
by lengthening the tube by means of what is
called draw-tube, and by use of an amplifer
where very great power is desired, we may have
a magnifying power in the same microscope
varying from five, or less, to TO- 600 diameter, or
more; but it is seldom use more than ], 900
diameters with profit. Most mcroscopical work
does not require an ampIifcation Of more than
400 to 500 diameters.
All material things visible to the naked eye
are aggregations, made up of parts The small
est particle that the eye can perceive is com
posed of a vast number of parts. The micro
scope, also reveals to us great number of ami
mails and plants so small that the unaided eye
cannot see them, yet these, too, are compound
and have many parts, yet are perfect and com
plete in themselves If we take drop of stag
nant water, not larger than o small pin-head
and examine it under sufficient power a great
variety of plant and animal life will, most likely
be revealed to us, of rare beauty and great ac-
tivity If it be particle of some stone that we
examine. we find thousands of exquisite shells
and remains of animal and plant life, which
lived, it may be, millions of years ago; if we
anime some minute part of the human body we
shall find glands, vessels, cells and structures
of great Importance, all most perfectly adapted
to their work; if it be a leaf, we find wonder
fully complicated network of cells, fbres, hairs
openings and vessels. Everything ex-
amined, under the magic power of
our microscope, reveals something new
something before unseen and unknown
A consideration that greatly recommends the
use of the microscope is the fact that it is never
bright for work. 1t works well by daylight or
lamplight. There is always something for ex
animation and study. By its use world of life
and beauty otherwise utterly unknowable. is
made known. Our ideas and notions of things
are greatly changed and enlarged. Plants be-
come living things, many of them marvellous
motions and powers We find them performing
most exquisite and graceful maneuvers, moving
in all directions, and travelling from place to
place. We find other plants living in wonder
fully beautiful glass houses, CEASED with lines
and sculptured as no human hand can scnlp
ture We see through and through plants and
animals and observe all their varied internal
structures and motions. In the series of articles
to follow this, / shall describe some of these
wonderful forms found everywhere about US. /
will also, from time to time, describe methods Of
work, and the uses of the microscope in daily
life, in detection of adulteration of foods and
medicines its uses in medicine, in the sciences
and, possibly, its bearings upon philosophy, and
scientific and religious theories Our pond and
river waters are SO full of minute life that we
hardly know where to begin to describe the
many interesting creatures we come across.
few days ago, in passing stagnant pond, / OBJ
served red scum covering quite an area. To
the unaided eye it looked like fine red dust
with here and there patches Of a greenish yellow
dust among it. / gathered small quantity of
the water in a small bottle and, at evening put
drop of it upon glass slide, slip Of glass one
by three inches, and laid very thin piece of
| glass over the drop gently. IA thin piece of
mica will do very well for cover glass;
drop Of water with powers ranging from seventy s
| five to 150O diameters, and the microscope soon
showed great number of slowly moving red
bodies of all shapes. Some were drawn out