the fociety a circumftance, which, though perhaps 

 familiarly known to theni, might, if more generally 

 divulged through the channel of their publications, 

 be of infinite advantage to the publick. 



In clearing my lands of the heaps of flones with 

 which this country every where abounds, I fouad 

 the quantity of gunpowder ufed in the operation to 

 amount to a confiderable fum at the end of the year j 

 and as the price of this article has been increafmg 

 of late to an enormous amount, I had recourfe to an 

 expedient by which the expence of it has been ma- 

 terially diminiflied. 



I weighed out two pounds of gunpowder, and one 

 pound of quick-lime well dried and. pulverized, 

 which after having been thoroughly mixed with each 

 other, I delivered to the blafter with directions to 

 apply it in fimilar quantities as he would have done 

 the powder by itfelf. I then felectcd fix of the 

 hardefl: granites I could find for the experiment, and 

 the effefts of the explofion were precifely the fame 

 as if powder alone had been ufed. It now occurred 

 to me that this might be fallacious, and that a fmaller 

 proportion of gunpowder would produce the fame 

 effefl as a larger ; I accordingly ordered the man to 

 bore holes in a fimilar number of ftones of the fame 

 texture and fize with the former, and to put in a 

 leflcr quantity of powder by one-third than he would 

 have done if it bad been left to his own manage- 

 ment. 



