Holding our razor firmly in the right hand we take our specimen in the thumb and index finger of the left hand. Place the side of the stem against the first joint of the index finger and slightly bend the tip of the finger round the object. The end of the stem, from which we propose to cut our section, should be slightly above the level of the index finger. With the thumb, the stem is pressed firmly against the first joint of the index finger and the first joint of the thumb must not be bent upwards. This last point is very important, as we shall see in a moment. From our description the method of holding the stem may seem somewhat cramped; it should not be so, however, and an easy position will help towards success but let it be the correct position. We may play the violin, in a manner, without learning the correct method of bowing but we can never become expert violinists unless we hold our bow properly, in the same way we can never cut really fine sections unless we hold our specimen in the correct way. We now lay our razor along the second joint of the index finger in such a manner that the heel of the razor, or a point near the heel comes gainst the end of the stem. For the first time we realize the importance of holding our specimen correctly, for the index finger forms a convenient platform on which to steady the razor. To cut our section, we, of course, press the razor towards us and, at the same time draw it outwards from heel to toe. We must never attempt to press the razor straight through the specimen, however soft the latter may be, we must always draw the razor along, at the same time as we press it through the specimen. Never cut outwards as in sharpening a pencil and never move the razor backwards and forwards as though using a saw. The outward cut will never result in a good section, a sawing movement will give a section alternately thick and thin. Should the section be somewhat tough we may find the razor slip suddenly over its surface, an event which will impress itself upon us painfully if we have forgotten the injunction not to bend the thumb, for the certain result of the slip will be the loss of a goodly portion of skin upon one’s joint. A straight thumb will be out of the danger zone of a slipping razor. [Illustration: _By the courtesy of Messrs. F. Davidson & Co._ 1. A FLY’S EYE A fly’s eye highly magnified, showing some of the many lenses of which it is composed. 2. IMAGES SEEN BY A FLY Photographs of a statue taken through a fly’s eye. Instead of seeing one image of an object, the fly sees as many images as there are lenses in its eyes. ]