THE MICHOSCOPE. 9 



leg of a fly, or of a beetle, clip it off, and put it under the 

 microscope. They are somewhat disappointed at seeing 

 indistinctly a row of black joints, and nothing more. 



Let that leg be first soaked for a few days in a little 

 potash and water, to soften it and dissolve the internal 

 substance; then washed in clean water and dried; then 

 soaked for a few minutes in turpentine, and finally mounted 

 in balsam : every joint will be clear, every hair visible, 

 the pulvillus transparent, and the structure admirably 

 displayed. 



The same results are obtained with the eyes, tongues, and 

 wings of all insects. 



The actual mounting is a matter of experience : to keep 

 out air bubbles is the great and only difficulty. 



Place a slide on the brass table, over the spirit lamp, and 

 when heated moderately put a drop of balsam in the centre 

 of it ; let this also become warm, but not very hot, and then 

 lay the prepared object in it. As bubbles arise, skim them 

 off with a needle, and take care that the balsam does not 

 boil, or your specimen is lost ; it will be full of obstinate 

 air bubbles, irrevocably fixed in the tissue. When it looks 

 clear, examine under the microscope, and if all right replace 

 it on the table, and having previously warmed a thin glass 

 cover, let it drop gently over the object. 



Dry it on the mantelpiece, or a stone slab, and then clean 

 the slide by scraping off the balsam and washing it with a 

 little turpentine; or soda and water will clean it nicely; 

 only if it is left in the solution, it will unsettle the balsam. 



Try experiments for yourself, and do not be discouraged 

 by a great many failures; neither be satisfied with bad 

 mounting, half-prepared objects, and untidy slides. 



