Improved Chemical Apparatus, &'c. c 55 



When tht inrtrumcnt is adjuftcd, which is done bv placino; 

 the weight W, hg. 1, at o on the hne of grains, and theu 

 (brewing or unlcrewing the counterbalance ball C, till the 

 tube T rife? ftowly into its harizontal pofition; then fet the 

 ball A at the diftance from the ball L that vou choofe, ami 

 the weight W placed at the divifion ornuniber of grains thac 

 you wifii the nrpuifive power of the eleitricitv to arrive at 

 before the drfcharge is made : this being done, connect the 

 battery or Jar wiTh the ball B bv means of the wire y, the 

 end of which goes into B at the hole X, and (liould ftund ac 

 riglit angles to B, the ball of v refting on the .jafterv: therr 

 connect the outtule of the battery or jar with the hook H; 

 as the batterv charges, the eleftn^meter Q. continues to rife; 

 and when it is fo highlv charged that the repullive power be- 

 tAvecn the balls L and F is ecjuul to the numhcr of grains at 

 which the weight W was placed, the ball L will defcend, and 

 deliver the chaj-ge of the battery to the ball A. The fubllance 

 or thing through which the fliock i's rntended to be palled, 

 niuft form part of liie communication between the hook 11 

 and the outfideof the batterv or jar. 



It is evident, from confidering the rnftiinnent. that it is 

 attended wrth thefe excellences ; that, the whole being com- 

 pact, the elecliic atmofphcre mull be fo alio: tharithas 

 but one i7ifid liion to di'pend upon; th^t the C(]uil:brJum of 

 the divided arm and ball may aiwsc)9 be .'Rljufted, confe- 

 f^uently the weight ufed know n to a certaintv ,* and the hook 

 for comnumicating with the outfide of the batterv bcin<» 

 placed on the foot of the iuftruinent, the communication niav 

 ))e made by wires h'in<: oi\ the table; which are bv far the 

 beft mode of conducting (hocks, as chains, by the imperfect 

 conneiSlion of their links (efpeci-allv if long), verv often, and 

 without being fulpefted, ^mdcr the fuccefs of many verv 

 well concerted experiments. 



XI-II. Defer ipt'ioji of an improved Che.7)iu-al Apparatus for 

 preferving feparale the Gufeous Produits evolved in manv 

 Proceffh: ; Sj which alfo Abjbrptlon is coinpletelj prevented, 

 and Liquids may be Jlronglj impregnated ivith the different 

 Gufes. ij/ \V. H. Pepvs Jw/i. £/ry.* 



JL ri E chemift, in his various refearches into the compo- 

 fition and quaUties of the numerous fubftances prefented by 

 Nature, had long to regret the waul of an apparatus capable 



* Communicated by the Author. 



of 



