206 Progress of Foreign Science. 
7.260 grains of phosphate of barytes. The liquid shewed a per- 
fectly neutral re-action, and was not precipitated by ammonia. 
The 7.260 grains of phosphate of barytes contain 2.309 grs. 
of phosphoric acid; whence the phosphate of soda is, by this 
analysis, composed, in 100 parts, of 
Phosphoricacid . 52.63 
Boda o 05) m0. caer 
According to the analysis of Berzelius, this salt contains, 
Phosphoric acid . 53.48 
Soda. . . . . 46.52 
and by his atomic determination it consists of 
Phosphoric acid . 53.30 
Boda 2.5) GT, 
The oxygen of the base is to that of the water in the ratio of 
1 to 12, by Berzelius. In the crystallized phosphate of soda, 
the oxygen of the base being to the oxygen of the acid as 1| to 
2%, and to the oxygen of the water as | to 12; the salt ought 
therefore to consist, according to Berzelius’s atomic numbers, of 
Phosphoric acid . 20.31 
SOG wake ath ca ures LAO 
NW AECE nae oe Prt, as Le 
100.00 
Of the Faces of the Crystals, and of their relative Situation. 
The primitive form of these two salts, is an oblique prism with 
rhombic bases, (Fig. 7). It is found usually with the faces 
f and ¢, (Fig. 8 and 9). The plane M’ makes with M” an angle 
of 67° 50’. The inclination of f to P was 129° 12’; and the 
inclination of P to the axis is consequently 58° 30’; and that 
of f to the axis 70° 42’*. 
I]. Caroric. 
M. Poisson read before the Academy of Sciences, on the 
3lst December, 1821, a memoir on the distribution of heat 
in solid bodies, of which an extract is given in the Annales 
de Chim. et de Phys. for April, 1822. He divides the subject 
into two parts; the formation of differential equations of the 
movement of heat, whether in the interior or on the surfage 
of solid bodies; and, secondly, the complete resolution of 
these equations, to deduce from them, at any instant what- 
ever, the temperatures of all the points of the body under 
consideration, according to that which they possessed at a 
determinate epoch. As far as we can judge from the extract 
made by the author himself, this memoir seems rather a display 
of his mathematical resources, than a contribution to physical 
knowledge. 
* The remaining abstract of this memoir, is reserved for the next 
Number. : 
