228 On the Pnndplts of Pump- Work. 



Exper'imnit T. 

 T!ie double lever (of iron) auJ both Us pistons weighed 

 irslb. : and less ihaa one pound weight laid upon the end of 

 the lever or handle, made it deseeud directly; which plainly 

 «hows the friction arising from the pressure of 200lb. is not 

 more than equal to one single pound weight ; a suffieient 

 proof of the great simplicity and perfection of the structure 

 of this pump. 



I^.rpfr'nnciit II. 

 After this, the axle was laid upon the surface of perpen- 

 dicular moving bars of tw^-lvc inches in length, which were 

 tantamount to friction wheels of two feet diameter; and it 

 was found that much about the same weight, viz. nearly one 

 pound, was then also necessary to nsake the end of the lever 

 preponderate. Whence it appears, that the friction of the 

 axle mav be entirely neglected, or, being so very small, may 

 be esteemed as nothing. 



This fact was also further verified by the men who worked 

 the pump J for tbev all unanimously declared, that they 

 found not the least diflerence whether they w'orked with the 

 friction bars, or without them. These are all convincing 

 proofs, that the construction of this pump is not liable to 

 the common objceiion of friction. 



As to the other imperfections of pump-work, viz. loss of 

 time, and which is unavoidable in common pumps, it is as 

 evident, that it can have no place here^ as being ineonsisteiit 

 with the verv eonstruetion of the pump ; for, since one pis- 

 ton or the other is always ascending, the water (conducted 

 in one pipe) Uiust be always rising; therefore no time can l>v 

 lost. 



Neither will the construction of this pump admit of any 

 water being lost in working it; for it is self-evident, that it 

 has such a structure of the pistons and valves, as necessarily 

 renders them not only w atcr-tight but air-tight likewise ; 

 and consequently no water is necessary, and no Lime lost, in 

 felchintr this pump, as is the case with all others of the 

 comTuon construclKUi. 



Lon-'" after this pump was erected, and its eflects publicly 

 shown, it was objected bv some, that the invention was not 

 new; for it could be pr()\ed that, years before, pumps had 

 been made with t.vo hirrels upon one pipe; and also that 

 leather had been applied to a piston for raising water without 

 friction before now. 'i'o all this I answer, 1. That I had 

 never heard oi' anv such construction of two barrels upon 

 Tine pipe, when hnade mine. 2. That upon hiquiry, I find 



