1 



relating to Air and JVater, 28 1 



began with this, with a view to afcertaiii whether any 'water 

 is produced when the air is made to dii-ippear in it. Accord- 

 ingly, into a glafs veflel containing 7 ounce meafures of pretty- 

 pure dephlogifticated air, I introduced a quantity of iron turn- 

 ings (which is iron in Imall tliin pieces, exceedingly conve- 

 nient for thefe and many other experiments) b.aving previoun>- 

 made them, together with the veflel, the air, and the mercury 

 by which it was confined, as dry as I poilibly could. Alfo, to 

 prevent the air from imbibing any moidure, I received it imme- 

 diately in the veflel in which the experiment was made, from 

 the procefs of procuring it from red precipitate; fo that it had 

 never been in contact with any water. ■ ~- ', t - 



I then fired the iron, by means of a burning lens, and pre- 

 fently reduced the 7 ounce meafures of air to .65 ; but I found no 

 more water after this procefs than I imagined it had not been 

 poflible for me to exclude, as it bore no proportion to the air 

 which had difappeared. Examining the refiduum of the air, I 

 found one-fifth of it to be fixed air, and when I tried the purity 

 of that which remained bv the teff of nitrous ain it did not 

 appear that aay phlogifticated air had been produced in the pro- 

 cefs : for though it was more impure than I luppofe the air 

 with which I began the experiment muft have been, it was not 

 more fo than the phlogifticated air of the 7 ounce meafures, 

 which had not been affeiled by the procefs, and which mufl: 

 have been contained in the refiduum, would neceflfarily make 

 it. In this cafe one meafure of this refiduum and two of ni- 

 trous air occupied the fpace of .32.- ' 



In another experiment of this kind, ten ounce meafures of 

 dephlogiflicated air were reduced to .8, and by wafhing in lime 

 water to .38. In another experiment, in which 7I ounce mea- 

 fures of dephlogiflicated air were reduced to half an ounce 

 Vol, LXXV". O o meafure, 



