26 
The solution of Bone Ash in Sulphurous Acid of IT 708 
specific gravity was found to contain in 1000 CC. 
Sulphurous Acid 
Sulphuric Acid . 
Phosphoric Acid 
Magnesia 
Lime 
141 '82 grm. 
trace 
47-42 
2-79 
59-69 
•n 
251-72 „ 
The formula 3CaO, P0 5 , 6 S0 2 requires for 47'42 P0 5 : 
Lime 55-78 grm. 
Phosphoric Acid .... 47*42 „ 
Sulphurous Acid .. . 127*50 ,, 
— 230-70 
The excess of Lime in the Analysis is 3-91 
and Magnesia 2-79 
These two would require Sulphurous Acid. . . 8*73 
Excess of Sulphurous Acid 5-58 
251-71 
The Bone Ash which was left undissolved by the 
Sulphurous Acid, had lost all its Magnesia, a circumstance 
which accounts for the large amount of Magnesia in the 
liquor. 
The proportion of 3CaO P0 5 and S0 2 varies according 
to the strength, of the liquor: if the latter is for instance 
1-060 specific gravity, 5eq S0 2 dissolve 3CaO, P0 5 , and in 
still weaker solutions we find only 4eq S0 2 for 3CaO, P0 5 
These solutions possess very interesting reactions, some 
of which are the following : 
A neutral solution of Ferric Chloride precipitates straw- 
colored Phosphate of Iron, and if added in proper quantity 
the liquor is free from both Iron and Phosphoric Acid. 
The precipitate, after washing and drying over Sulphuric 
Acid is free from Lime and Sulphurous Acid. Its analysis 
agrees well with the formula Fe 2 0 3 , P0 5 -f 5HO. 
Acetate of Copper colours the Sulphurous Acid solution, 
when added in small quantity, intensely green, a further 
