6179. To Mount Small Insects for the Microscope

6179.   To Mount Small Insects for the Microscope. Mounting small insects for the microscope, such as parasites and acari from birds, beetles, etc., may be performed by placing the live insect on the inside of a sheet of tolerable good note paper, folded, and when in the act of running, (losing the paper and pressing it tightly in a book. By this means the legs and antennae may be nicely extended, all the expressed moisture absorbed by the paper, and the skin left apparently unbroken. It should be allowed to remain in the book about 2 days, when it may be carefully removed from the paper, put in a turpentine bath, and afterwards mounted in balsam in the usual way. (See No. 6180 (To Mount Microscopic Objects in Canada Balsam).)

6180. To Mount Microscopic Objects in Canada Balsam

6180.     To Mount Microscopic Objects in Canada Balsam. "Warm the glass slips, etc., to a temperature just below the boiling heat of water. If there is any doubt of the balsam penetrating all the interstices and readily adhering to the specimens, it will be well to pour a few drops of clear turpentine upon the specimens, which will greatly facilitate the taking of the balsam; the latter, however, must not be used until the turpentine has nearly evaporated. The moment when the balsam is to be added with the best effect can only be known by experience. Clear old Canada balsam is the best suited for these purposes. When used it must also be heated to a temperature just below boiling water, and then poured upon the object, previously arranged upon a slip of glass. The top slip of glass, which is usually smaller and thinner than the under one, is now to be placed upon it; one end of each slip being brought into contact first, and then the other allowed to fall upon it. By this means no air-bubbles will be enclosed. The exact quantity of balsam must be learned by practice. Of two faults, namely, too much or too little, the former is to be preferred. Be careful not to press the glasses together too hard, otherwise, on the removal of the pressure, the air will enter between the glasses, and the preparation will be spoilt. Having thus mounted the object, it must be slowly dried in a warm situation. This will take 1 or 2 days; after which the slide is to be cleaned by scraping off the surplus balsam with a strip of plate glass. Finally, wipe it clean, using first a linen rag moistened with turpentine, and then a piece of dry clean leather.

6181. Marvels of the Microscope

6181.    Marvels of the Microscope. A beautiful and easily produced exhibition of crystal formation may be seen under the microscope as follows : Upon a slip of glass, place a drop of liquid chloride of gold or nitrate of silver, with a particle of zinc in the gold and copper in the silver. A growth of exquisite gold or silver ferns will vegetate under the observer's delighted eye.

6182. To Prepare a Skeleton

6182.    To Prepare a Skeleton. After cutting off as much flesh and cartilage from the bones as possible, boil them in water till the remainder easily separates. The French still further prepare their skeletons by bleaching for a short time in a weak solution of chloride of lime.