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Information for students and teachers on how to work with microscopes.
How to Work With a Microscope
One of the first requisites for the proper use of the microscope, is a thorough knowledge of its parts and an acquaintance with the optical principles involved. For this purpose the writer earnestly requests a perusal of the preceding pages, and is convinced that in cases where no previous knowledge of the instrument has existed, work will be .done with far more ease, in much less time, and with a greater degree of satisfaction. Ignorance of the instrument's capacity may lead to an idea that it is inferior and thus be the means of its final abandonment ; and in place of the anticipated pleasure there may arise a feeling of bitterness and disappointment for all future with everything connected with it. There are innumerable cases of this kind and they have induced a belief that it is difficult to acquire a practical manipulation of the microscope, whereas such is not the case when a limited time, properly applied, is devoted to it. Working Table for Microscopy A firm table should be used, preferably one with three legs, as this will always be firm no matter how uneven the floor is, and if it can be arranged, should be devoted to this purpose only. One with a round or square top of three feet provides ample room. Although not necessary, a table with a revolving top, provided with clamp, is very convenient, as with this two or more persons may make observations without changing their seats. A very neat arrangement for a table-top is that suggested and used by Dr. J. E. Reeves. He places upon an ordinary table three or four thicknesses of white paper and upon these a plate of polished glass as large as the top ; this can be procured of almost any glazier at a low price. It is pleasant to work upon and will not soil. As in almost all cities there is more or less continual vibration from wagons upon the paved streets, the writer suggests an effectual remedy. Take a thin board, say half an inch thick, of a sufficient size to receive the microscope ; fasten on the upper side at two opposite ends, cleats of 1 inch square and counter-sink into these through the board four spiral springs of such tension that when they bear the weight of the instrument, the bottom of the board will be about \ inch from the table. Have the working table provided with drawers and arrange receptacles for the accessories, secure from dust, but at a convenient point to reach. When the instrument is not in use put it into its case or cover it in a manner so that it shall be free from dust. For this purpose a large bell glass is best. Room to Conduct Microscopy If possible to use a mirrored microscope, a room should be selected facing the north, as the light in this direction is most constant. It will prove a great saving of time if all or a portion of it can be permanently arranged to receive the entire working outfit. It should also be chosen with a view to its being free from disturbance. Light for Microscopy If using a mirror microscope as stated, the light from the northern sky is most desirable, and that from a white cloud is preferable to that from a blue sky. On account of its intensity, direct sunlight should seldom be used ; but if modified by a white curtain or reflected from a white wall it is excellent. For lamp light an ordinary flat wick kerosene or student lamp is well adapted. The Hitchcock lamp, from its better combustion is still better, as its color more nearly approaches white. The ideal artificial light is that from an electric light. Gas light is not desirable as it is seldom sufficiently steady.
Position of Light for Microscopy The relation of the microscope to the source of light is principally a matter of personal convenience if you are using a mirrored microscope. With daylight it makes little difference whether it is at the front or side of the instrument, although the writer prefers it at the front, as the manipulation of the object does not obstruct it ; but the lamp should be placed at the right or left side within, easy reach of the hand for the purpose of controlling it. The writer suggests that the beginner make it a habit at the outset to place it on the side of the instrument opposite to the unoccupied eye, as the tube then places the latter in the shadow. Which Eye to Use with a Microscope In a binocular instrument both eyes are used, but in a monocular only one is used, and it depends upon a trial which is best suited. A large proportion of persons are afflicted with astigmatism, often without knowing it, and when this exists it may be in one eye or when in both, may be to a greater extent in one than in the other. Its presence may prevent the eye from observing fine detail ; but whichever eye is found to be best suited should be used. When both eyes are alike it is sometimes advisable to change from one to the other. It should be made a habit at the outset and strictly adhered to, to keep both eyes open.A little difficulty may be found to do this, as the eye which is free will probably observe the objects upon the table ; but as soon as the mind becomes fixed upon what it sees in the microscope, this impression disappears. After a time it will be found to require no exertion and will certainly add to the ease and comfort of the manipulator while working. Order for Microscopy Among the requisites for successfully prosecuting work with the microscope are a strict observance of the instructions, even if they appear superfluous, a systematic way of doing work, and cleanliness. Have a place for every article which is required, so that the hand may immediately be placed upon it ; after it has been used clean it before putting it aside ; keep strange hands from your apparatus unless you are assured that a knowledge of its manipulation exists. Material to Use in Microscopes Although the purpose of this manual is to be a guide to the intelligent use of the microscope and not the preparation or preservation of objects, it may not be out of place here to enumerate what every owner of an instrument should have at the outset. The first should be a book on objects giving proper instruction on their preservation. There are many of these, and all of them good. Next in order, slides, covers and labels are necessary. As covers are easily broken in cleaning, a larger proportion of them will be necessary. A cabinet for slides, a large variety of which may be selected from, will aid in starting work in a systematic manner. Forceps and a small pipette are indispensable. For preserving objects, Canada balsam or damar should be purchased, while the other necessary material which may be gleaned from the instruction book is easily obtainable. When it is intended to do section-cutting a good mechanical microtome, not necessarily expensive, should be obtained at the outset.
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Microscope Technique 
