56 ON SOME NEW POBMS 



research by the examination of some others in my 

 possession. 

 1. Phosphate of Lime (unitctire.) Plate V. Fig. 3. 

 The representative signs of these crystals with the 

 indications of the principle angles, are, 



MBP 

 MafP 



Inclination of M upon P 90° 

 M upon M 120° 

 a? upon P 140 47' 

 x upon M 129 i3' 



The faces x being formed by the decrement of a 

 single range of molecules, I have termed it Phosphate 

 of lime (imiiaire) according to the nomenclature of 

 Mr. Hauy. 



2. Phosphate of Ltme (unitave compressed.) 



The crystals are sometimes so much llattened or 

 compressed, as to put on the appearance of an eight 

 sided table with bevelled ed^es. In this case the two 

 opposite faces of the prism M offer square surfaces 

 at the same time that the faces P P, and four of the 

 faces of the hexaedral prism are linear. 



Besides these two varieties there occurs in the same 

 matrix, crystals of the primitive form, varying from 

 one tenth of an inch to au inch ; as well as in rouuded 

 pieces. Indeed nearly all the crystals present some 

 of their edges rounded, and particularly the margins 

 of the summits, so that they often have the appearance 

 of hexaedral prisms terminated by rounded summits. 



