214 



The Microscope. 





shows on its crystals indentations, a condition represented in no 

 other butter yet observed. The butter crystals seen in the but- 

 ter made at Mr. Frank Ward's dairy, from milk of Alderney cows, 

 of Washington, also different in some particulars from all others 

 examined, being darker in color, spines longer, and of larger 

 size. Specimens intended for permanent use should be mounted 

 with a varnish ring, to prevent the cover from pressing on the 

 crystals, and to prevent the movement of the cover used to pro- 

 tect them. 



I have examined quite a number of other fats, vegetable 

 and animal, and find, thus far, that animals and vegetables of 

 distinctly different genera, and even species, yield fats which 

 give typical fatty crystals characteristic of the animals and 

 plants which yield them, and I am confident that this new dis- 

 covery will prove highly useful to microscopists and chemists 

 when investigating adulterated substances used as food or in 

 medical preparations. 



o C S$f&°°QO 

 ° r ooSc? c oooo 



° & 0O O 0°OO O( ? 



°oV %°oo 

 °Q^o o o0 



Fig. 1.- 

 Fig. 2.- 



Fig. 3.- 



Fig. 4.- 



Fig. 5.- 

 Fig. 6.- 

 Fig. 7.- 

 Fig. 8.- 



-Represents crystals of boiled butter as seen by a pocket lens. 



-A single crystal of butter, highly magnified, viewed by transmitted light 

 only. 



-A crystal of butter viewed by polarized light only. It exhibits the cross of 

 St. Andrew. 



-A crystal of butter as seen under polarized light and selenite plate. In this 

 case beautiful colors are displayed, while the cross is but faintly seen. 



-Represents what seems to be a budding butter crystal. See description. 



-Represents the rosette crystals of butter. 



-The crystalline form of lard. 



-The crystalline form of beef. 



Double Staining. — A good example is seen in double stain- 

 ing the frond of a fern with logwood and aniline blue ; the sort 

 taking the latter, and standing out brilliantly on the general 



