got Priestley’s Experiments and Obfetvations 
loofe, or only united to water ; and perhaps future experi- 
ments may difcover the operation of this circumftance. 
There is fome analogy between the experiment of the calx 
of iron imbibing inflammable air, and the iron itfelf imbibing 
dephlogifticated air. In the former cafe water is produced, and 
in the latter fixed air. However, this cafe of iron imbibing 
dephlogifticated air more nearly refembles the cafe of the blood 
in the lungs imbibing the fame kind of air, and in both the 
cafes as dephlogifticated air is imbibed, fixed air is formed. 
This, therefore, feems to be a confirmation of the conclufion 
which I drew from my former experiments on blood, viz. that 
it parts with phlogifton in refpiration. Only I would now 
add, that at the fame time that it parts with phlogifton it takes 
in dephlogifticated air, which makes the cafe perfectly fimilar 
to that of the experiment with iron , which likewife parts with 
phlogifton to form fixed air, at the fame time that it imbibes 
dephlogifticated air in contact with which it is fufed. 
I propofe to referve for a future communication the conti- 
nuation of thefe experiments, containing an account of the ap- 
plication of the fame procefs to other fubftances ; but it may 
not be amifs juft to mention a few of the general refults, and 
thofe which have the neareft connexion with the experiments 
recited above. 
After having tranfmitted ftearn in contafr with charcoal and 
iron in a copper tube, I propofed to do the fame with other fub- 
ftances containing phlogifton, and I began with bones , which 
we re burnt black, and had been fubje&ed to an intenfe heat, 
covered with fand, in an earthen retort. From three ounces of 
bone thus prepared, and treated as I had done the charcoal, I 
got 8 40 ounce meafures of air, with the lofs of 288 grains of 
water. The bones were by this means made perfectly white, 
2 and 
