1317.) during the Year 1816. 39 
Phosphate of Soda. 
ve ae dia aie sie oe werd OO ven wa jertr on 
TSASE us) cheated a eee fs 87. a ulate 3°925 
Phosphate of Lead. 
Acid ret tte nina tition « Ee \ 1) REPRESS RC * 
(OT. i Ae bon cide Wei e) aah oho 14:00 
MRE ae an om cee sual LU atime oO 
BE haa ach «= ae atts). Sy A MW sts, 
80 RA so 
Phosphate of Silver. 
MRR | | aarti ee BN BR Se ae 
REPT cess 4 ATA 16 .... 14°75 14°75 + = 
It is quite clear from these analyses that the equivalent number 
for phosphoric acid is 4*5. 
But according to Berzelius, phosphoric acid is a compound of 1 
atom phosphorus + 5 atoms oxygen, and it is composed of 100 
phosphorus + 126*94 oxygen. According to this estimate, an atom 
of phosphorus weighs 3-93, and an atom of phosphoric acid 8°93— 
a number quite inconsistent with the preceding equivalent, and 
undoubtedly wrong. My number 3°5 is likewise wrong, but the 
error is much less. 
Berzelius has likewise analysed two of the phosphites. Let us see 
what equivalent namber will result from these analyses for phospho- 
rougacid. He found these salts composed as follows :— 
Phosphite of Barytes. 
GIA. os, wieitists + >> aise LOO 
Phosphite of Lead. 
ee ce cela x ane PUY IAT ih i Be, 
RARE SL ss ee a lara! Misia wate’ ons 405'48 .... . 14 
Is it not obvious that $°5 is the equivalent number for phospho- 
yous acid? ‘This is the number which I gave in my paper on phos- 
phureted hydrogen as the equivalent for phosphoric acid. I am in- 
clined at present to suspect that what I took for phosphoric acid was 
in reality phosphorous acid, and that my phosphorous acid was the 
hypophosphorous acid of Dulong. If shall verify this suspicion as 
soon as I have as much leisure as will enable me to undertake the 
requisite experiments. Were the supposition well founded, the 
composition of the three acids would be as follows :— 
* By my analysis. 
