On th!B Manufacture of Gunpowder, 355 



tuit. Oxygen and hydrogen airs have the same basis, water. 

 Oxygen and hydrogen, as solid bases, are, consequently, non- 

 entities. Positive and negative electricity are distinct fluids. 



As these two electricities change water into two airs, and 

 as those airs can from water be obtained in any proportion, 

 and as those airs can be united, and again form water and 

 fire; I consider those electricities as theprinciples of fire. 



I consider, therefore, that the influence is excited by the 

 decomposition of heat, caloric, or fire 3 as the tourmalin de- 

 composes it by merely heating it. 



The elastic state of aeriform bodies does not depend so 

 much on the quantity of vvhat is termed latent heat, as on 

 the nature of one of the principles of heat which it contains. 

 The solid oxygen, according to the Lavoisierian hypothesis, 

 in nitre, contains as much latent heat as in the state of gas. 



Put a piece of red-hot iran on an electrometer, and drop 

 la little water on it, does not hydrogen air escape ? Now, as 

 positive electricity and water form hydrogen air, does not the 

 electrometer show signs of negative electricity ? 



XLIV. On the Manufacture and constituent Parts of Gun- 

 poivder. Read before the Askesian Society May 1801. By 

 Mr, R. Coleman, of the Royal Mills, Waltham Alley, 

 a corresponding Member of the Society. 



J. HE process of manufacturing gunpowder is so inaccu- 

 rately described in every author which I have seen, and in 

 many instances so extremely absurd an account is given, that 

 I am induced to hope that a true account thereof will not be 

 unacceptable ; and more particularly as I apprehend nothing 

 tan tend more to establishing a true theory of the combustion 

 of gunpowder, than a knowledge of the ingredients it is com- 

 posed of, and the manner of their combination. With this 

 view I have drawn up the following account of the process, 

 &c. in manufacturing that article, and added some facts on 

 the explosive force thereof, which I now beg to lay before the 

 Society. 



Yy2 On 



