MICROSCOPICAL TECHNIQUE 45 



placed film side down on a clean slide, avoiding air bubbles 

 by allowing first one side of the cover glass to come in con- 

 tact with the slide, and then gradually lowering the cover 

 glass into place. The excess of water is removed and the 

 upj>er surface of the cover glass dried by blotting with filter 

 paper. The preparation is now ready to be examined directly, 

 or a permanent preparation may be made by allowing the 



FIG. 11. STAINING DISH AND DROPPING BOTTLE FOR STAINS 



An enameled-ware basin covered with J-inch-mesh galvanized 

 wire cloth 



cover glass to air dry after staining and washing. On a slide 

 place a small drop of Canada balsam dissolved in xylene, and 

 then lower the cover-glass preparation, film side down, on to 

 the drop. The balsam should be of such consistency that it 

 will spread under the weight of the cover glass, and should 

 be present in such quantities that it will fill the space be- 

 tween the cover glass and slide to the edge of the cover, 

 but not run beyond. The preferable method is to make a 

 preliminary examination of the preparation in the water 



