relating to Air and Water „ gop 
bined with it, as the water itfelf brings along with it, as an 
eflential ingredient in its compdfition. For in one experiment 
296 grains added to the weight of a quantity of iron by fleam, 
made it to yield about 1000 ounce meafures of inflammable air. 
This would weigh 60 grains, and one-fifth of the 296 grains 
of water will be 59.2 grains. Again, 267 grains added to iron 
by fleam made it to yield 840 ounce meafures of inflammable 
air, which would weigh 50.4 grains, and one-fifth of the 267 
would be 53.4 grains. 
When the experiments on the melting of iron in. dephlo- 
■gift icated air Aiall be repeated on a larger fcale, which it will 
not be difficult to do by the help of a larger burning lens than 
I am at prefent pofiefled of, it will be eafy to reduce thefe cab 
eolations to a greater certainty. All that I can do at prefent is 
to approximate to fuch general conclufions as I have mentioned 
but they are of fo much confluence in philofophy, that it 
will certainly be well worth while to afeertain them with as 
much accuracy as poffible. Nice calculations would be ill be- 
■flowed on the imperfefl data which I am as yet able to furnifh. 
Attention muft alfo be given to the quantity of water contained 
in inflammable air from iron ; which not being yet afeertained 
ds not confidered in thefe inferences. I wifh only to hint in 
this Poflfcript, that fome important conclufions feems to be 
nearly within our reach* 
"% ND OF > ARt I. OF VO L. LXJIV. 
