41 8 Dr. priest l E"V*s Experiments relating in Phlogifton , 
always fome lofs of the earth in the cloudinefs of the air, 
whenever the produdtion of It was rapid. In a future procefs I 
had abundant proof that the air did not come from any earthy 
matter with which the water had been combined. 
Hitherto I had no idea but that all that was neceffary to the 
converfion, as I concluded it to be, of water into air, was to 
give it a red heat, without which it would not quit the calca- 
reous earth ; and I imagined by this means the matter or prin- 
ciple of heat was fo intimately combined with it, as not tobefe- 
parated from it by cooling, as in the cafe of fleam. But I, as 
well as all my friends, was a long time utterly difconcerted 
upon finding that when I put the whiting and water into a 
coated glafs retort, the water came over in the form of fleam, 
and little or no air was produced. The refult was alfo the fame 
when I made the procefs in a gun- barrel, in a porcelain retort* 
or even in an earthen retort glazed in the infide. 
That the earth had not lofl its property of doing its part in 
the bufmefs, I found by putting more water to the fame whiting 
which had failed in the glafs retort, and which had been ufed 
no lefs than four times before, and then heating it in an 
earthen retort ; when again it gave air only, and no water, the 
fame as before. And at this time I obferved, that part of the 
air was hardly to be diflinguifhed from that of the atmofphere. 
I cannot exprefs my furprife at my unexpedted failure with 
the glafs retort ; and my lpeculations on the fubjedl were va- 
rious, but at that time altogether ineffedtual. Among other 
things it occurred to me that, poftibly, fome phlogifton, either 
contained in the earthen retort, or coming through it (though 
1 could not tell how, or on what principle) from the fire, might 
be neceffary to water, and all other fubftances, affuming the 
form of air. But when, with this idea, I put fpirit of wine, 
oil, 
