**To avoid breaking a cover slip and/or microscope slide while focusing (more importantly scratching a lens), first locate the specimen using the low-power objective, and then switch to the higher power objective. 

**Never focus the high power objective with the coarse adjustment knob, and never use these lenses when examining thick specimens or whole mounts of specimens. 

**To avoid dropping the microscope or banging it against a laboratory bench, carry the microscope in an upright position using both hands. 

**When carrying the microscope, place one hand on the base and the other hand around the arm. 

**DO NOT PLACE THE MICROSCOPE IN AN UPSIDE DOWN POSITION. PIECES WILL FALL OUT. 

**Keep microscope away from the edge of the bench, particularly when not in use. 

**Make sure power cords are out of the way. 

**Never force the microscope parts to work. 

**Never dismantle the microscope. 

**Use lens cleaners and paper both before and after use. 

**Take all slides off the stage prior to storage. 

**Always store the microscope in low power objective. 

**Place the cover over the microscope after each use. 

**Bring all defective microscopes to your instructors attention. 

## PARTS OF A COMPOUND MICROSCOPE: 

Eyepiece/Ocular Lens: The eyepieces  are the lenses you look through. The eyepiece of most binocular microscopes can be adjusted to match the distance between the eyes of different observers (interpupillary adjustment). Other microscopes may have different magnifications which are stamped on the side of the eyepiece. Most are 10X. You may have to remove the eyepiece from its holder to determine its magnification. 

Record the magnifying power of the eyepiece.________________ 

Body Tube: Light travels from the objectives through a series of magnifying lenses in the body tube to the ocular. In some microscopes, the body tube is straight; in others, the oculars are held at an angle. The body tube contains a prism that bends the light rays so that they will pass through the oculars. 

Objective Lens: Attached to a rotating nose piece, or turret , at the base of the body tube are a group of 3 or 4 objectives. Locate the turret and notice a click as each objective snaps into position. 

The objective lenses  focus the light that comes through the specimen, up the body 

