k 



318 PHILOSOPHICAL TRANSACTIONS. [aNNO 1760. 



Air from marble let up ^1000 



391 473 391 473 527 40 



143 133 534 606 394 45 



284 115 818 811 I89 45 



194 80 1012 891 109 46 



The apparatus used in this experiment was sufFererl to remain in the same 

 situation till summer, when the thermometer stood at 65". The bulk of the 

 air from sugar, not absorbed by the water, was then found to be 287 ; so that 

 the matter had remitted 235 parts of air. The bulk of the air from marble 

 not absorbed, was 194; so that 85 parts were remitted; which is therefore a 

 proof that water absorbs less fixed air in warm weather, than in cold. It appears 

 from this experiment, that the air produced from sugar by fermentation, as 

 well as that discharged from marble by solution in acids, consists of substances 

 of different nature: part being absorbed by water in greater quantity than the 

 rest. But, in general, the air from sugar is absorbed in greater quantity than 

 that from marble. In forcing the air from sugar into the cylindrical glass, no 

 sensible quantity of moisture was found to condense on the surface of the quick- 

 silver, or sides of the glass; which is a proof that no considerable quantity of 

 any thing except air could fly ofi" from the sugar and water in fermen- 

 tation. 



Exper. 4. — ^The specific gravity of the air produced from sugar, was found in 

 the same way as that produced from marble. A bladder holding 102 ounce 

 measures, being filled with this kind of air, lost 29-J- grains on forcing 

 out the air, the thermometer standing at 62° and the barometer at 29-1. inches. 

 Whence, supposing the outer air during the trial of this experiment to be 826 

 times lighter than water, as it should be, according to the supposition made use 

 of in the former parts of this paper, the air from sugar should be 554 times 

 lighter than water. Its density therefore appears to be much the same as thai 

 of the air contained in marble; as that air appeared to be 51 1 times lighter than 

 water, by a trial made when the thermometer was at 45"; and 563 times lighter, 

 by another trial when the thermometer was at 65°, This air seems also to 

 possess the property of extinguishing flame, in much the same degree as that 

 produced from marble; as appears from the following experiment: 



Exper. 5. — A small wax candle burnt 15' in a receiver filled with -jV of air 



from sugar, the rest common air. In a mixture containing ^"j- or — • of air 



from sugar, the rest common air, the candle went out immediately. When the 

 receiver was filled with common air only, the same candle burnt 72'. The 

 receiver was the same as that used in the former experiment of this kind, and 

 the experiment tried in the same way, except that the air from sugar was first 



