( 3°5 ) 

 Ko. XXXVII. 



General Principles and ConflrtiBion of a Sub-marine Vejfel, 

 communicated by D. Bufincll of ConneBictit, ihc inventor, 

 in a letter ofOElober, 1787, to Thomas Jefferson then 

 Minijler Plenipotentiary of the United States at Paris. 



Read June 'T^HE cxtemal fhapc of the fub-marine veiTel 

 8, 1798- X bore lome refemblance to two upper tortoife 

 fhells of equal lize, joined together; the place of entrance 

 into the veifcl being reprefented by the opening made by the 

 fwell of the Ihells, at the head of the animal. The iniide 

 was capable of containing the operator, and air, fufficient 

 to fupport him thirty minutes without receiving freih air. 

 At the bottom oppofite to the entrance was fixed a quanti- 

 ty of lead forballaft. At one edge which was dircdtly be- 

 fore the operator, who fit upright, was an oar for rowing 

 torward or backward. At the other edge, was a rudder for 

 ileering. An aperture, at the bottom, with its valve, was 

 defigned to admit water, for the purpofe of defcending; and 

 two brafs forcing-pumps ferved to eje£t the water v/ithin, 

 when neceflaryfor afcending. At the top, there was like- 

 wiie an oar, for alcending or defcending, or continuing at 

 any particular depth — A water-gauge or barometer, <deter- 

 mincd the depth of defcent, a compafs diredlcd the courle, 

 and a ventilator within, fupplied the veiTel with frefli air, 

 wlien on the furface. 



1 he entrance into the veflel was elliptical, and fo hnall 

 as barely to admit a perlon. This entrance was furrounded 

 with a broad elliptical iron band, the lower edge of which 

 was let into the wood of which the body of the veflel was 

 made, in fuch a manner, as to give hs utmoft fupport to 

 the body of the veflel againft the preflure of the water. 

 Above the upper edge of this iron band, there was a brafs 

 crov\fn, or cover, refembling a hat with its crown and brim, 



which 



