(Jacob Rumans) #1

Now move the curved side of themirroruntil it catches the light and
directs it up into the tube, throughthe eyepiece orocularinto your eye.
Place yourpreparedslide in the centerofthestageover the hole. As you
watch the shorter, low power objective,turnthe larger wheel, orcoarseadjust-
ment,until it isabouta quarterof an inch away from the slide on the stage.
Putyour eye to the ocular. Slowly raise the tube, orbarrel,byturning
the coarseadjustmenttowardyou. The specimen on the slide will gradually
come into clear view orfocus.
When the specimen is focused, switch to thefineadjustment. Keep your
eye at the eyepiece. Turnthe small wheel, or fine adjustment, very slowly
until the magnified specimen comes into view with increasing clearness.
The lens in the eyepiece, orocular,of most microscopes will magnify an
object ten times. The lens in the low power objective will magnify ten times,
also. Therefore, if you use the low power objective, the specimen on the slide
willappear10 x 10 or 100 times its actual size.
The lens in the high power objective usually magnifies forty times. There-
fore, if you use the high power objective, the specimen on the slide willappear
10 x 40, or 400 times its actual size.
Workwith your microscope until you cancoordinatethe movementsof
its various parts. A good specimen for practice is a tiny scrap of newsprint.

Materials:A scrap of newsprint with the letter"e"on it.
Follow this procedure: Place the newsprint in the middle of a glass slide.
Lay a cover slip over it. Place the slide on the stage of your microscope so
thatthe newsprint is over the opening. Switch to low power and look at it.
You will observe:The"e"will look upside down andbackwardand much


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