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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- 

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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 

