46 Improvements in Physical Science [JAN. 
always slightly, either as an acid or alkali. According to the analysis 
of Berzelius, it is composed of 
Phosphoric acid ........-. 20°33 .... 100 
Soda, » Mids wae bce vhion «1 Ope amanouasa 
Watermartcctistea contact se 62°00 
100-00 
A biphosphate of soda likewise exists; but Berzelius did not 
analyse it with precision. 
(5.) Phosphate of Lime.—Berzelius has met with so many ano- 
malies in his experiments on the combinations of phosphoric acid 
and lime, that he has been able to form no satisfactory conclusion. 
When a solution of phosphate of soda is poured into a solution of 
neutral muriate of lime, the liquid loses its neutrality, and acts as 
an acid on vegetable blues. A crystallized precipitate falls, which 
was composed of 
Phosphoric acid ........ 41°90 .... 100°00 
byme: +s. 28.30. Visor 35°42" REO TB PS 
Waterss) o2s50¢3525 322272268 
100°00 
If muriate of lime be poured into phosphate of soda, and the 
precipitate be digested in the excess of phosphate of soda, a phus- 
phate of lime is obtained possessed of very different properties. It 
is gelatinous, like alumina, and was found composed of 
Phosphoric acid .......... 45°57 .... 100 
ROME ase Sais Shes Alae p Rains AG Iate, «& E 
Water sis) caddatupinas ele 11 RFD 
It does not appear necessary to state the cther experiments which 
he made on the phosphates of lime, as the results obtained are so 
anomalous that no other conclusion can be drawn from them than 
that most of the substances examined by Berzelius were rather mix- 
tures than true chemical compounds. His observations on my un- 
published experiments strike me as somewhat premature, as he can- 
not possibly be acquainted with the method which I followed. 
Indeed, had he even heard my paper read to the Royal Society last 
winter, he could have known but a very small part of the very 
numerous experiments which I made on the phosphates. This 
defect in the paper was one of the reasons that induced me to with- 
draw it; though my principal motive was some new views which 
had occurred to me after that paper was read, and which I con- 
ceived would enable me to add considerably to its accuracy. Ber- 
zelius’s experiments will be very useful in that point of view, as 
they draw the attention to a variety of particulars which I had over- 
looked. _ L hope hereafter to be able to resume the subject with 
additional advantages, In the mean time I may just say that I still 
4 
