16 THE MICROSCOPE. Jan., 



PRACTICAL SUGGESTIONS. 



ByL. A. WILLSON, 



CLEVELAND. OHIO. 



Metallic Globules. — Very interesting and pretty slides may 

 be made from condensed volatilized metals. Gold that con- 

 denses from the melting pots of the mint forms microscopic 

 globules of gold. On the roof of copper-smelting works a fine 

 black appearing dust is found which under the 'scope is shown 

 to be globules of metalic copper and when viewed as opaque 

 objects exhibit the light red metallic lustre of copper. Many 

 of the globules are hollow. 



Vertical Illuminator. — This accessory is of very limited 

 utility. In the hands of an expert manipulator it will grandly 

 show the lines on an opaque silver-plated Amphipleura pelucida 

 and will reveal a few other opaque objects with high powers. 

 In the hands of an amateur it is but an aggravation of spirit. 

 It does not work at all satisfactorily with dry lenses. It is 

 suitable only for objects mounted dry on the cover and with 

 immersion lenses. 



Daphnilla Tuckermanii. — When a filtering of water supply 

 from the Great Lakes is poured into a glass most of the diatoms 

 and the heavier material fall to the bottom but little specks are 

 always found floating on the surface. The specks generally 

 contain some of the most interesting and wonderful forms in 

 the gathering. In this way I recently had the pleasure of ob- 

 taing this strange and complicated Crustacean. Remove the 

 specks with a spatula to a cell, cover and examine with an inch 

 objective. The little thing was so interesting that I mixed gly- 

 cerine with the water and mounted it permanently. 



An Elegant microtome. — Possessing an old fashioned sec- 

 tion cutter, that c )st 815 some years ago, and finding that, in 

 my hands, it was absolutel}^ worthless for any fine or accurate 

 work, I committed it to the tender mercies of a scientific young 

 machinist. 



He made a very heavy iron casting with a V shaped opening, 

 into this he inserted a V shaped sliding portion for a knife car- 

 rier ; firmly attached the old section cutter to the heav}^ casting ; 

 furnished brass screws and clamps. When a proper knife was 

 screwed to the carrier, the old section cutter was transformed in- 

 to an elegant accurate and efficient modern microtome and at a 

 trifling expense. 



