122 Mr. Stenhouse o?i Artificial Oil of Ants. 



but of from one to two lines in size ; colour grass-green ; 



transparent at the margins; lustre vitreous; of the hardness 



of topaz; specific gravity 3"594<. According to two analyses 



performed by Prof. H. Rose, it consists of 



Magnesia 26'77 27*49 



Lime 0-27 — 



Peroxide of copper ... 0"27 0"62 



Alumina 64-13 57*34 



Peroxide of iron 8*70 14-77 



100-14 100-22 



resembling, therefore, spinelle and zeylanite, and belonging 

 with these, since it likewise coincides in its crystalline form, 

 to the same genus. Locality, Slatoust. 



Xanthophyllite, so named from its wax-yellow colour and la- 

 minar structure, constitutes a new genus. In thin leaves trans- 

 parent ; on the surface of fracture it has a strongly nacreo- 

 vitreous lustre. Hardness that of felspar ; specific gravity 

 = 3-044. Before the blow-pipe it proved to contain alumina, 

 lime, soda, peroxide of iron and silica, but no fluoric acid, 

 magnesia or potash. It occurs near Slatoust. 



PIKROPHYLL. BY A. P. SVANBERG. 

 [From Poggendorff's Annalen, vol. 1. Part 4.] 

 This new mineral occurs near Sala. Structure foliated ; 

 hardness between that of mica and calcspar ; specific gravity 

 2-73 ; colour, very dark green. Analysis gave 



Oxygen. 



Silica 49-80 25-88 1 



Alumina Ml 0-52/^'''^"" 



Lime 0-78 0-22] 



Magnesia 30-10 11-65 ^3-43 



Protoxide of iron 6-86 1-56J 



Protoxide of manganese a trace 

 Water 983 



98-48 8*73 



whence the mineralogical formula 3 MS^ + 2 Aq. 



XXIIL On Artificial Oil of Ants, By 3. Stenhouse, Esq.* 



IT was first observed by Da;bereiner, when preparing formic 

 acid by the action of sulphuric acid and oxide of manga- 

 nese on sugar, that the liquor which distilled over contained 

 * Communicated by the Author. 



