CHAPTER IV 
HOW TO USE THE MICROSCOPE 
In beginning work with the compound microscope, place 
the base of the microscope opposite your right shoulder, if you 
are right-handed; or opposite your left shoulder, if you are left- 
handed. Incline the body so that the ocular is on a level with 
your eye, if necessary; but if not, work with the body of the 
microscope in an erect position. In viewing the specimen, keep 
both eyes open. Use one eye for observation and the other 
for sketching. In this way it will not be necessary to remove 
the observation eye from the ocular unless it be to complete 
the details of a sketch. 
Learn to use both eyes. Most workers, however, accustom 
themselves to using one eye; when they are sketching, they use 
both eyes, although it is not necessary to do so. 
Open the iris diaphragm, and incline the mirror so that 
white light is reflected on the Abbé condenser. Place the slide 
on the centre of the stage, and if the slide contains a section 
of a plant, move the slide so as to place this specimen over the 
centre of the Abbé condenser. Then lower the body by means 
of the coarse adjustment until the low-power object, which 
should always be in position when work is begun, is within one- 
fourth of an inch of the stage. Then raise the body by means 
of the coarse adjustment until the object, or objects, in case a 
powder is being examined, is seen. Open and close the iris 
diaphragm, finally adjusting the opening so that the best pos- 
sible illumination is obtained for bringing out clearly the struc- 
ture of the object or objects viewed. Then regulate the focus 
by moving the body up or down by turning the fine adjustment. 
When studying cross-sections or large particles of powders, it 
is sometimes desirable to make low-power sketches of the speci- 
men. In most cases, however, only sufficient time should be 
spent in studying the specimen to give an idea of the size, struc- 
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