The Miceoscope. 



107 



3. Chemically pure glycerin, to be kept in a glass- stoppered bot- 

 tle. In fact all bottles used for holding reagents, stains, etc., and em- 

 ployed for microscopical purposes, should, if j^ossible, be provided 

 with glass-stoppers. Wherever cork is used, even though the bottle- 

 contents have no corroding effect iipon it, small pieces become de- 

 tached and dirt ivill get into the bottles. However, for glycerin and 

 a few reagents to be mentioned hereafter, dropping bottles with 

 glass bulb, as here ligiu'ed, will prove extremely con- 

 venient. They cost about 25 cents apiece. 



4, 5 and 6, The salt solution should be prepared 

 with distilled water. A convenient receptacle for the 

 distilled water is what is known to chemists as a wash 

 bottle. One can be obtained at low cost from any 

 druggist. As ether is very volatile, the bottle contain- 

 ing it should be carefully stoppered. 



Teasing. — The art of teasing is a much neglected 

 one. There is a beauty, a completeness, an appar- 

 ently clear exposition of parts in a well-cut and stained 

 section that lead many to adopt this manner of pre- 

 paring all tissues for microscopical examination. 



When, however, one desires to study individual cells or tissues, teas- 

 ing will be required that they be isolated and thus placed at the best 

 advantage for study. Again, many softer substances cannot be cut 

 at all, nor can they be hardened sufficiently for the purpose. Here 

 teasing will do much better service than the one often employed — 

 squeezing and crushing the specimen between cover and slide — 

 which not only often distorts the parts and cellular elements beyond 

 all recognition, but render it very opaque. It is urged, therefore, that 

 beginners, and, for that matter, many who are more advanced, culti- 

 vate not only the art of teasing, but of recognizing the various ele- 

 ments so isolated. Such a course will do much to give a better 

 understanding of various structures, and will lead to a knowledge of 

 minutise which could never be learned from a study of sections how- 

 ever well prepared. It is a matter of stu-prise, then, that the method 

 is so little employed, and this surprise is increased when one consid- 

 ers that the method is simplicity itself. It is this simplicity which 

 leads us to choose its practice for the first working lesson. 



From a piece of fresh nerve, or, if this is not easily obtainable^ 

 from the nerve preserved in Muller's fluid and alcohol, with 

 scissors, snip, longitudinally, a thin strip about ^ inch in length. 

 Place a drop of the sodium-chloride solution in the center of a clean 

 slide (see hints for method of cleaning slide and cover-glass). Now, 



