340 On the ConJiruB'ion of Gal'vanii: CofnhinatioHS. 



of exHtence it may poflibly be poflefled of greater, and of dif- 

 ferent powers. 



But, independent of the immediate applications of this 

 fcience, much is to be hoped from the elucidations which it 

 may bcftow upon the kindred fciences. And a difcovery fo 

 important as to excite our allonidiment, cannot fail of be- 

 coming;, at fome period, ufeful to fociety. All the different 

 branches of human knowledge are intimately connected to- 

 sether, and theoretical improvements cannot well be made 

 m them without being accompanied by practical advantages. 



Royal liUtuution, Sept. i, iSoi. 



LIV. Aji Accomit of a Method of covfruB'mg Sitmple and 

 Compound Galvanic Combinations, tulthout tl:e Ufe of Me- 

 tallic Suh/hmces, by meatis of Charcoal and different Fluids. 

 By Mr. Davy *. 



„!• xFca piece of well burned charcoal be brought in contaft 

 at one of its furfaces with a portion of water, and at another 

 furface with a portion of nitric acid, a fimple galvanic com- 

 bination will be formed when the two fluids are connected 

 together : and the powers of it arc demonftrated by its agen- 

 cies upon the limbs of frogs, and by its effetts upon the organs 

 of fcnie. 



2. A compound galvanic combination or a galvanic bat- 

 tery may be formed from a number of feries compofed of the 

 fame fubrtances : but in this cafe the fluid elements of each 

 feries, not being immediately in contaft, mull be conne£fed 

 with fimilar elements in other feries in an order of regular 

 alternation, fuch as water, charcoal, acid ; water, charcoal, 

 acid ; and fo on. 



3. The bell mode that has yet occurred of conflru£ling 

 galvanic batteries with charcoal, is by means of a number of 

 olaires, which are made to contain, alternately, nitrous acid 

 and water, and which are connc6ted in pairs by means of 

 moiltened cloth. The pieces of charcoal ufcd are made from 

 very denfe wood, fuch- as box or lignum vita? ; and in this 

 cafe, the fluids will not penetrate into them by capillary at- 

 tra6lion much beyond the places of their primary conta6i. 

 Their forms arc thofc of arcs, fo that each piece connects 

 tocrether two glafles; but in inftances where fingle pieces of 

 charcoal cannot be obtained of the proper fliape, two long 

 and thin flips may be faftened together by filk, fo as to form 

 the angle neceflary to their infertion into the glalfes. 



• From t'le fame. 



4. Twenty 



