SUB-MARINE VESSEL. 309 



and the powder ; the hogOiead was loaded with ftones as 

 deep as it could fwim ; a wooden pipe defcending thi'ough 

 the lower head of the hogfliead, and through the plank, 

 into the powder contained in the bottle, w\ts primed with 

 powder. A match put to the priming, exploded the pow- 

 der, which produced a very great efFecl, rending the plank 

 into pieces ; demolifhing the hogfhead ; and carting the 

 ftones and the ruins of the hogfhead, with a body of water, 

 many feet into the air, to the aftonifliment of the fpecfta- 

 tors. This experiment was likewife made for the fatisfac- 

 tion of the gentlemen above mentioned. 



I afterwards made many experiments of a fimilar nature, 

 feme of them with large quantities of powder ; they 

 all produced very violent explofions, much more than fuf- 

 ficient for any purpofe I had in view. 



In the firfi: eflays with the fub- marine veflel, I took care 

 to prove its ftrength to fuftain the great preifure of the in- 

 cumbent water, when funk deep, before 1 trufted any per- 

 {on to defcend much below the furface : and I never fuffer- 

 ed any perfon to go under water, without having a ftrong 

 piece of rigging made faft to it, until I found him well ac- 

 quainted with the operations neceflary for his fafety. Af- 

 ter that, I made him defcend and continue at particular 

 depths, without rifmg or fmking, row by the compafs, 

 approach a veffel, go under her, and fix the wood-Jcrew 

 mentioned in No. 2, and marked A, into her bottom, &c. 

 until I thought him fufEciently expert to put my defign in- 

 to execution. 



I found, agreeably to my expedlations, that it required 

 many trials to make a perfon of common ingenuity, a 

 Ikilful operator : the firft I employed, was very ingenious, 

 aiid made himfelf mafter of the bufinefs, but was taken fick 

 in the campaign of 1776, at New-York, before he had an 

 opportunity to make ufe of his (kill, and never recovered 

 his health fufficiently, afterwards. 



Experiments 



