12 On the transmission 



phlogifticated ; and from the calx that fublimed I got 

 6 ounce meafures of nitrous air, and 15 of dephlo- 

 gifticated. 



9. That quicklime gets weight by expofure to the 

 air is well known. The following experiment will 

 fliew what that weight is. 



An ounce of quicklime expofed in a {hallow difh on 

 the I fl of July increafed in weight till the 14th of 0£t. 

 when it had gained 320 grains. Another ounce had gain- 

 ed 300 grains in the fame time, and after this they gained 

 nothing more. In the fame time an ounce of quick- 

 lime faturated with water, and then left to dry, had gain- 

 ed 294 grains : another ounce gained exactly the fame 

 weight, and a third 325 grains. 



10. Pyrophorus is generally made with the charcoal 

 of vegetable or animal fubftances mixed with alum, or 

 any thing that contains the acid of vitriol, and the heat 

 by which it takes fire is occafioned by the eager at- 

 traftion of this acid for water. I accidentally found that 

 a pyrophorus may be made of fiilphur and iron. 



Having kept a cup full of this mixture made up with 

 water in a quantity of common air about two months, 

 1 then took it out, and left it in the cup. The next day 

 perceiving the cup to be warm, 1 emptied it upon a 

 board, when it grew hot, fmoked very much, gave 

 out a ftrong fmcll of vitriolic acid air, and at length be- 

 came red hot. Putting a part of it into another cup 

 confined by common air, the air was rapidly dimi- 

 nifhed. 



1 I . Of the abforption of Jixed air by a mixture of iron 

 flings and fulphur. 



Among fome of the firfl of my experiments were 

 feme on the effed: of this mixture on fixed air, as well 

 as on that of the atmofphere. The following relate 

 to the fame fubjedt, and may deferve to be profecuted 

 further,. 



A 



