490 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



hole is below the bottom of the slit. The compressor is now inverted, 

 and a bottle or tube, made to fit watertight, and having a small hole in 



the side at the bottom, is inserted in 

 the well. The hole in the bottle 

 and that in the bottom of the groove 

 are plugged with cotton- wool, either 

 loosely or tight, according as the 

 flow of water is desired. The water 

 flows through the hole in the bottle, 

 and then through that in the bottom 

 of the groove, and so between the 

 glass covers containing the object, 

 passing out through the slit and the 

 hole in the cap. The flow can be 

 so regulated that it may take either 

 a day or an hour to empty the bottle, 

 which will contain about one fluid 

 ounce. The cotton-wool plugs com- 

 pletely stop any foreign substance 

 passing. When observation is re- 

 quired, the bottle being removed, 

 the water will remain in the life-box, or it may be at once rendered 

 watertight by turning the hole in the cap away from the slit." 



Schieck's Microscope Lamps. — Herr J. W. Schieck has devised the 

 lamps shown in figs. 81-4. 



Fig. 81. 



Fig. 82. 



The pecularity of the two former (which differ only in their mounting) 

 is the metal shade and reflector, which is shaped as shown in the figs. 



