tN SOME CHEMICAL AGENCIES OB ELECTRICItY, 335 



hy meaas of fusion with boracic acid : it afforded in 100 ActVm of eieso 



parts Sf parts of soda, and nearly { a part of muriatic ^^^^^^^ *" ^^' 

 r z ir 7 ^ i r- Composing coqjjb 



acid, withi 15 parts of lime. This stone appeared to me pounds. 

 Tery well fitted for the purpose of experiment: cavities 

 were drilled in two pieces, properly shaped ; they contain, 

 ed about 12 graias of water each ; they were connected by 

 moistened amianthus, aud the process conducted as wsns^ 

 with a power of 50 pairs of plates. At the end qf ten 

 hours the result was examined with care. The fluid that 

 had been positively electrified had the strong smell of oxi- 

 muriatic acid, and copiously precipitated nitrate of silver ; 

 the other portion of fluid alFected turmeric, and left by 

 evaporation a substance which seemed to be a mixture of 

 Jime and soda. 



A part of a specimen of compact zeolite, from the Giant's 

 Causeway, which hy analysis had given 7 parts in 100 of 

 soda, had a small cavity made in it ; it was immerged in 

 pure water in a crucible of platina, and electrified in the 

 same manner as the cube of Carrara marble, mentioned in 

 page 328. In less than two minutes the water in the cavity 

 had gained the property of changing the colour of turme- 

 ric; aad in half an hour the solution was disagreeably 

 alkaline to the taste. The matter dissolved proved to be soda 

 and lime. 



Lepidolite, treated in the same way, gave potash, 



A piece of vitreous lava, from Etna, gave alkaline mat- 

 ter, which seemed to be a mixture of soda, potash, aud 

 lime. 



As in these trials the object was merely to ascertain the 

 general fact of decomposition, the process was never con- 

 ducted for a sufEcient time to develope a quantity of alka- 

 line matter capable of being conveniently weighed, and of 

 course any loss of weight of the substance could not b^ 

 determined. 



I thought it right, however, to make one experiment of 

 this kind, for the sake of removing every possibility of 

 doubt on the source of the diflisrent products ; and I se* 

 lected for this purpose glass^ as a substance apparently in, 

 soluble iu water, and not likely to afford io auy way er- 

 roneous results. 



