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7) Turn the focusing knob until the objective lens is almost touching the slide. Don’t let the lens touch
the slide as you may break the slide and damage the lens. Now look through the eyepiece and
slowly turn the focusing knob back until you see the sample clearly.
How to make your own prepared slides
Samples for examination should be very thin so that light can pass through them. If the sample is too
thick it will appear dark in the microscope.
There are thousands of common items around the house and in the yard that can provide interesting
samples. To name just a few you could start with cloth fibers, hair, plant or vegetable leaves, grass,
paper, onion skin, pollen, dust, salt crystals, and even water!
If the sample is very thin and lacks color, a drop of red or blue dye can help make details show more
clearly. To prepare the dyes in your set add enough warm water to half fill the dye bottles. Replace
the lids tightly and shake well until the dye crystals are all dissolved. You can transfer a drop of dye
from the bottle to your slide with the pipette.
Always be careful when using the dyes as they can stain clothing, furniture, or carpets.
Making a Temporary Slide
A) Start with a clean blank slide. Clean slides are important. If your slide is dusty or dirty, you
should clean it with a soft cloth, so that you do not also magnify dirt or dust along with the
sample you want to view. This can be distracting and even confusing!
B) Prepare a thin sample. You may have to slice it with the scalpel. Always be very careful. You
should ask for adult help when using sharp objects.
C) Pick up your sample with the tweezers and put it on the center section of the slide. Add one
drop of water. To enhance viewing you may add a drop of dye instead of water.
D) Gently place a slide cover over the sample, being careful not to allow any air bubbles in.
E) Remove any excess water or dye with a piece of paper towel by pressing it down gently over
the slide cover.
F) Now you can observe your slide.
