246 



SLIDES AND COVER-CLASSES 



[CIL IX 



earths. The slips of greenish glass, while not as neat or desirable for general 

 microscopy, seem to be decidedly more resistant, and are therefore preperable.'' 

 Transparent celluloid slides are recommended by Behrens for work where hy- 

 drofluoric acid and its derivaties are to be examined. (Chaniot, Jour, Appl. 

 Micr. vol. iii, p. 793) . 



\ 330. Cleaning Slides for Ordinary Use. Place new slides that are to be 

 wiped at one sitting in a glass vessel of distilled water containing 5,, ammonia 

 (Fig. 188-189). F r wiping the slides use a so-called glass towel or other well 

 washed linen towel. One may avoid large wash bills by using absorbent gauze.* 



In handling the slides grasp them by the edges. Cover the fingers 

 of the right hand with the wiping towel or the gauze and rub both faces 

 with it. When wiped thoroughly dry, place the slide in a dry glass jar 

 like that shown iu Fig. 189, or for larger numbers use a museum jar (Fig. 

 190). Soap and water are also recommended for new slides. 



\ 331. Cleaning Used Slides. If only watery substances or glycerin or 

 glycerin jelly have been used one may soak the slides over night in ammonia 

 water, then changing the water for fresh and wiping as described iu ? 330. 



When balsam or other resinous media ($ 353) have been used it is best to 



c 



FIG. 188. Round glass aquarium jar suited for an 

 aquariutn, for cleaning slides or for any other purpose 

 where a wide open glass dish is needed. 



FIG. 189. Covered glass dish knozun as an ''ointment 

 jar" of the right height to hold slides on end. (Cuts 

 j./6, 147 loaned by the Whitall Tatum Co. ) . 



* The gauze mentioned is No. 10, "Sterilized absorbent gauze", of the 

 Griswoldville Mf'g Co. of N.Y. It is sometimes called bleached cheese cloth. 

 In the author's laboratory it is cut into pieces, 1 4, /i, y 5 of a yard. When a 

 piece is soiled it is thrown away. 



