[87] 



Art. XIX. On a Method of Augmenting the Force of 

 Gunpowder. 



Extract of a Letter to the Editor, from Colonel Gsorok Gibbs. 



J. EMPLOYED, the last year, a man in blowing rocks, and 

 having seen an account of a method of substituting a portion of 

 quick lime for a part of the gunpowder usually employed, I was 

 induced to make a number of experiments upon it. I now 

 send you the results in the certificate of the person employed, 

 whose statement might be relied on, even if 1 had not super- 

 intended myself a number of the experiments. 



" Sunswick Farms, Oct. 19, 1817. — I certify that, having been 

 employed by Colonel Gibbs in blasting rocks on his farm, I, by 

 his orders, made use of a composition of one part quick lime 

 and two parts gunpowder, and uniformly found the same charge 

 to answer equally well with a like quantity of gunpowder. I 

 made upwards of fifty blasts in this manner, as well as several 

 hundreds in the usual way, and can therefore depend upon the 

 accuracy of this statement. I found, however, that when the 

 powdered lime was mixed with the gunpowder the day before, 

 that the effect was diminished. It should be always used the 

 day it is mixed. 



(Signed) T. Pomeroy." 



This preparation was made generally in the morning, put in 

 a bottle and well corked, to prevent the access of the external 

 air. The rationale of the process was not explained in the 

 original recommendation, but it soon occurred to me, that it 

 must be owing to the desiccation of the gunpowder by the 

 lime. 



The attraction of moisture by gunpowder, is known to be 

 very great : according to Rees's Cyclopedia, upwards of 16 

 per cent, has been absorbed, and that the removal, simply,, 



