168 PROCEEDINGS OF THE CALIFORNIA 



water, at an incipient red heat. In the platina forceps, it fuses with intu- 

 mescence, at about 2. of Von Kobbell's scale, tinging the flame with the pecu- 

 liar green characteristic of phosphoric acid. The button formed by fusion, 

 crystallizes on cooling, showing numerous brilliant facets. Readily soluble, 

 even in coarse crystals, in dilute nitric and hydrochloric acids. 



A qualitative analysis, revealed the presence of Lime, Phosphoric acid, and 

 water, with barely discernable traces of Magnesia and Alumina. 



The quantity of mineral at my disposal was very small, scarcely exceeding 

 one gramme in weight. In each of the following analyses, the water was de- 

 termined in 0.2 grammes, the remaining 0.3 grammes being employed in the 

 determination of the Lime and Phosphoric acid. The results were as follows 



1. 2. 



Lime 32.65 32.73 



Phosphoric acid 41.50 41.32 



"Water 26.33 26.40 



100.48 100.45 



These figures agree exactly with the composition of the neutral tri-basic 

 phosphate of lime (2 CaO., H O* P 5 ), with the addition of four equivalents 

 of water of crystallization, (2 CaO, HO,P0 5 }4 aq.) viz. : 



2 CaO 56.26 = 32.59 



PO s 71.36 = 41.34 



H0 9 -°°l 26.07 



} - 



4Aq 36.00 



172.62 100.00 



In the polarizing microscope, the mineral shows a vivid succession of colors. 

 A sample has been sent to Prof. J. D. Dana, who has kindly undertaken the 

 study of its crystallographic characters, and I hope, in a short time, to be able 

 to communicate the results of his investigations to the Academy. 



It is with very great pleasure, that I dedicate this species to Prof. Geo. 

 J. Brush, of Yale College, to whose unwearied zeal and efficient labors, Ame- 

 rican Mineralogy stands so deeply indebted. 



Regular Meeting, Sept. 19th, 1SG4. 

 President in the Chair. 



i 



Seven members present. 



Prof. Rudolpho H. Philippi, of Santiago, was duly elected 

 an honorary member, and Mr. W. B. Ewer, of this city, a 

 resident member of the Academy. 



