THE WISCONSIN FARMER.



SCIENCE, ART, STATISTICS.

           The Craig Xieroscope.

  We cannot interest the curious, inventive,
and knowledge-loving portion of the commu-
nity more than by giving them a description
of a new microscope. lately patented and in-
troduced into public notice. It is, indeed, a
new revelation to the natural vision, and opens
up and extends indefinitely the field of obser-
vation and investigation. It is thus described
by one who has used it and who knows its
merits:
   i This beautiful and useful instrument was
patented on the 18th day of February last.
The microscope, as the reader is aware, is an
instrument used to magnify minute objects; it
ieveals whole races of living beings which the
unaided eye has never seen, and enables us to
behold tbe wonderful beauty and adaptation
to the purposes for which they were intended,
of the most minttte parts of animal and vege-
table organizations. No field of inquiry is
mote iltvitittg and promises a richer harvest
than that which is opened up by the micro-
scope, and few departments of education are
more itttportant and interesting than this.
  - There are two kinds of microscopes, de-
nominated simple and compound. In a simple
microscope we look directly at an object
through a single lens, whereas in a compound
microscope there are two glasses-one near
the object and the other near the eye-and the
focus is adjusted by changing the position of
one of the glasses. So much time, skill, and
patience are required to use a compound mi-
croscope, that it has never come into popular
use, notwithstanding the wonderful interest
which attaches to microscopic investigations.
   The simple microscope, if of a high power,
 can be used with but very little satisfaction
 and comfort, owing to the fact that both the
 object and the eye must be very near the lens,
 and it is difficult to get and retain the focus
 during the examination, as every one is aware
 who has attempted to use the little lens set in
 a plate of silver or other metal. But we have



now in the -Craig Microscope," an instru-
ment which requires neither skill nor experi-
ence, and but very little time and patience, to
make numerous examinations of microscopic
objects. Although it has but one lens, yet its
shape and composition are new, and practical-
ly it stands midway between the simple and
compound microscope; and the serious obsta-
cles, named above, to the general use of either
of these instruments, are obviated in this new
microscope.  The lens is neatly mounted in
hard rubber, at the summit of the instrument;
the stand is either of brass or rubber, about
five inches high; the focus is on the under or
flat surface of the lens, the object glass is
placed immediately beneath the lens, and, two
or three inches below this, there is a mirror to
reflect the light on the under surface of the
object and lens.  The magnifying power of
this instrument is greater than that of the
cheapest compound microscope, and in fact is
just about the power most frequently required
in making microscopic examinations, and the
inventor has had the good sense to offer it to
the public at a very low price-simply two
dollars.
  "d There is no end to the objects suitable for a
microscopic examination-they are innumera-
ble. Take, for illustration, a common house-
fly. Now, the reader must not expect to be
able to place a whole fly in the focus of a mi-
croscope which magnifies one hundred diame-
ters, for the field is not large enough-the
higher the power the smaller the field of



228



r-