largerthanit appearsto your unaided eye. Underhigh power youwon'teven
see the"e"as a letter! Ithas been magnified so many timesthatit shows up
as heavy black lines crossed with fibres of the paper.
As you already know, the"e"is magnified 100 timesunderlow power of
the microscope, 400 times under high power. Itappears to be upside down
and backwardsbecause straight light rays from the "e" on the slide pass
through the double convex lens in the objective and are bent. (Light
waves passing from athinnermedium, such as air, to a denser medium, in this
case a solid glass lens, are always bent.)
These bent light rays converge (come to a point) in the microscope tube.
They thencontinueinto the slightly curved lens in theocularand up into your
eye (see diagram).
OBSERVING ASINGLE HUMAN HAIR
Materials:All you will need besides your microscope, a glass slide and a
cover slip is a lonestrandof hair.
Follow this procedure:Pull a hair out of your scalp. Place it in the middle
of the glass slide and cover it with a cover slip. Put thepreparedslide on the
stage of your microscope.
Use low power first, and then high power.
You will observe:A long shaft composed of two layers. The pointat
which the hair wasattachedto the scalp is cuplike and is called aroot.