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fectly. Now you can tighten the screw. The lighting is switched on when
you turn the switch on the microscope base.
Now you can observe in the same way as described in the previous
section.
TIP: The higher the magnification you use the more light is required for
a good illumination of the picture. Therefore, always start your experi-
ments with a low magnification.
5. Condition and prepare viewed objects
5.1. Condition
This microscope features transmitted light, so that transparent speci-
mens can be examined. If opaque specimens are being examined, the
light from below goes through the specimen, lens and eyepiece to the eye
and is magnified en route (direct light principle). Some small water organ-
isms, plant parts and animal components are transparent by nature, but
many others require pretreatment — that is, you need to make a thinnest
possible slice of the object by hand cutting or using a microtome, and
then examine this sample.
5.2. Creation of thin preparation cuts
Specimens should be sliced as thin as possible. A little wax or paraffin is
needed to achieve the best results. Put the wax into a heat-safe bowl and
heat it over a flame until the wax is melted. You can use a candle flame
to melt the wax.
DANGER!
Be exremely carfeful when dealing with hot wax, as there is
a danger of being burned.
Then, dip the specimen several times in the liquid wax. Allow the wax that
encases the specimen to harden. Use a MicroCut or other small knife or
scalpel to make very thin slices of the object in its wax casing.
DANGER!
Be extremely careful when using the MicroCut, knife or scalpel.
These instruments are very sharp and pose a risk of injury.
Place the slices on a glass slide and cover them with another slide before
attempting to view them with the microscope.
5.3. Creation of your own preparation
Put the object to be observed on a glass slide and cover the object with a
drop of distilled water using the pipette (21).
Set a cover glass (available at a well-stocked hobby shop) perpendicular
to the edge of the water drop, so that the water runs along the edge of the
cover glass. Now lower now the cover glass slowly over the water drop.
6. Experiments
What you need to know
Caution!
When using your experiment set, wear an apron (or old clothing) and rub-
ber gloves! Always carry out your experiments under the guidance and
with the help of an adult!
GB
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