300 Dr. Priestley's Experiments and Ohfei'vations 



rated with water, is expofed to heat m inflammable air, this 

 air enters into it, deftroys the attraction between the water and 

 the earth, and revives the iron, while the v>^ater is expelled in 

 its proper form. 



Confequentiy, in the procefs \mt\\Jieam, nothing is neceffary 

 to be fuppofed but the entrance of the water, and the expul-* 

 fion of the phlogiflon belonging to the iron, no more phlo- 

 gifton remaining in it than what the water brought along with 

 it, and which is retained as a confiituent part of the water, 

 or of the new compound. 



Having procured water from the fcales of iron (which I muft 

 again obferve is, in all refpe6ls, the fame fubftance with iron 

 melted in dephloglfticated air, or fatu rated with fteam by means 

 of heat) and having thereby converted it into perfe6l iron again, 

 I did not entertain a doubt but that I (hould be able to produce 

 the fame effe6l by heating it with charcoal in a retort; and I 

 had iikewife no doubt but I fhould be able to extract the addi- 

 tional weight which the iron had gained (viz, one-third of the 

 whole) in water. In the former of thefe conjectures I was 

 right ; but with refpe6: to the latter, I was totally miftaken. 



Having made the fcales of iron, and alfo the powder of 

 charcoal very hot, previous to the experiment, fo that I was 

 fatisfied that no air could be extrafted from either of them fe- 

 parately by any degree of heat, and having mixed them toge- 

 ther while they were hot, I put them into an earthen retort, 

 glazed within and without, which was quite impervious to air. 

 This I placed in a furnace, in which I could give it a very 

 ftrongheat; and connected with it proper veffels to condenfe 

 and collect the water which I expelled to receive in the courfe 

 of the procefs. But, to my great furprife, not one particle 



of 



