1200X Microscope Manual
object, clean the slide and cover slip, dispo-
sing of the specimens.. One of the secrets of
successful observation with a microscope is
the use of clean slides and cover slips. Spots
or stains will distract you when looking at an
object.
Permanent Prepared Specimens
Permanent prepared specimens are produ-
ced from objects that you would like to look
at again and again. The preparation of dry
objects (e. g. pollen or the wings of a fly) can
only be done with special glue. You’ll find
such glue at a local hobby store or online,
identified as “gum media.” Objects that con-
tain liquid must first have the liquid taken out
of them before they can be prepared as per-
manent specimens.
How to Prepare a Dry Object
First, place the object in the middle of a clean
slide and cover it with a drop of glue (gum
media). Then place a cover slip on top of the
object and glue. Lightly press the cover slip,
so that the glue spreads to the edges. Let the
specimen harden for 2-3 days before obser-
ving it.
How to Prepare a Smear Specimen
For a smear specimen, place a drop of the
liquid to be observed (e.g. water from a pudd-
le in the forest) on the end of the slide using
a pipette. Then smear the liquid across the
slide with the help of a second slide. Before
observing, let the slides dry together for a few
minutes.
Experiments
Experiment 1:
Black - and - White Print
Objects:
1. A small piece of paper from a newspaper
with a black and white picture and some text.
2. A similar piece of paper from a magazine
with color pictures and text.
In order to observe the letters and the pictu-
res, produce a short-term slide from each ob-
ject. Now, set your microscope to the lowest
magnification to look at the specimen from
the newspaper. The letters on the newspaper
look frayed and broken, since they are prin-
ted on raw, low-quality paper. Now look at the
specimen from the magazine. The letters on
the magazine specimen look smoother and
more complete. The pictures in the newspa-
per are made up of many tiny dots, which ap-
pear slightly smudgy. The halftone dots of the
magazine picture are clearly defined.
Experiment 2:
Color Print
Objects:
1. A small piece of color - printed newspaper
2. A similar piece of paper from a magazine
Make short-term specimens from the objects
and observe them with the lowest magnifica-
tion. The colored halftone dots of the newspa-
per often overlap. Sometimes, you‘ll even noti-
ce two colors in one dot. In the magazine, the
dots appear clear and rich in contrast. Look at
the different sizes of the dots.
Experiment 3:
Textile Fibers
Objects and accessories:
1. Threads from various fabrics (e.g. cotton,
linen, wool, silk, rayon, and nylon)
2. Two needles
Place each thread on a separate slide and
fray the samples using the two needles. Next,
wet the threads and cover them each with a
cover slip. Set the microscope to one of the
lower magnifications. Observe each slide in
turn. Cotton fibers come from a plant and look
like a flat, twisted ribbon under the micro-
scope. The fibers are thicker and rounder at
the edges than in the middle. Cotton fibers
are basically long, collapsed tubes.
Linen fibers also come from a plant, and they
are round and run in one direction. The fibers
shine like silk and exhibit many bulges along
the length of the thread.
Silk comes from an animal and is made up of
solid fibers that are small in diameter, in con-
trast to the hollow plant-based fibers. Each
fiber is smooth and even and looks like a tiny
glass tube.
The fibers of the wool also come from an
animal. The surface is made of overlapping
sleeves that look broken and wavy. If pos-
sible, compare wool from different weaving
mills. In doing so, take a look at the different
appearance of the fibers. Experts can deter-
mine which country the wool came from by
doing this.
Rayon is a synthetic material that is produced
by a long chemical process. All the fibers
have solid, dark lines on the smooth, shiny
surface. After drying, the fibers curl into the
same position. Observe the differences and
the similarities between the different types of
fibers.
Experiment 4:
Table Salt
Object: Common table salt
Place a few grains of salt on a slide, and ob-
serve the salt crystals with the lowest setting
of your microscope. The crystals are tiny cu-
bes and are all the same shape.
Experiment 5:
Production of Salt Crystals
Objects and accessories:
1. Table salt
2. A graduated cylinder filled halfway with
warm water to dissolve the salt
3. Cotton thread
4. Paper clips
5. A matchstick or pencil
Add salt to the water until the salt will no
longer dissolve. You now have a saturated
salt solution. Wait until the water has cooled.
Attach a paper clip to the end of the cotton
thread. The paper clip serves as a weight.
Tie the other end of the cotton thread into
a knot around the match, and dip the end
with the paper clip in the salt solution. Place
the match horizontally on top of the test
tube, which prevents the cotton thread from
slipping all the way down into the test tube.
Now, place the tube in a warm place for 3-4
days. If you take a look at the glass after
a few days under the microscope, you can
see that a little colony of salt crystals has
formed on the cotton thread.
Experiment 6:
Raising Brine Shrimp
Accessories:
1. Shrimp eggs (at your local hobby store)
2. Sea salt
3. Hatchery
4. Yeast
Artemia salina are a species of shrimp
typically found in salt lakes, bodies of water
with a higher salinity than even the ocean.
During a drought, a salt lake can become
a hostile habitat for organisms, and entire
populations of Artemia salina sometimes
die off. During drought conditions, to ensure
that the species will repopulate the salt lake
when the drought ends, Artemia salina lay
thick-shelled eggs called winter eggs that
can survive for up to ten years in a dormant
state. Winter eggs can withstand heat, cold
and chemicals. These eggs hatch when
favorable conditions return to their ambient
environment. The eggs provided (23d) are
of this type.
Incubate Your Brine Shrimp
To hatch the shrimp, create a solution with
an appropriate salinity and temperature.
First, fill two containers with a half litre of
freshwater, and let them both stand for
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