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hitrous air occupied 0.953 an ary of 
with two meafures of nitrous air?® 2 - 
1.92. By Abbé Fontana’s. method"? 
it gave 1.903 1.965; 2.95. -- 205 
Thus this air feemed to furpafs 
far the goodnefs of common air. 
t11. I then tried it by the flame 
of a candle, and found it to ex- 
plode with a very loud report. As 
I thought the e refult of thefe trials 
cation oF nitrous air to the ‘teft 
of any air, I repeated each of thefe 
experiments twice, and obtained 
conftantly the fame refult. 
112. I was refolved, however, 
to bem again the experiment: 
me plants of Perficaria urens were 
pee har gallon jar, and a good 
quantity of pure air was let up in 
- the jar. It was kept in the open 
air from Sunday till Friday follow- 
S 2 ing, 
