New method i pegimiptsing Silicates. 323 
and charged a battery ina ‘short time. The strap was twe enty- 
four feet | long, six inches broad, and one eighth of an.inch thick. 
It crossed in the middle between the two drums, the’strap form- 
ing a figure eight. Here then was considerable friction, since 
the strap made one hundred revolutions in a minute. 
In the American Journal of est for July, 1840, is mention- 
'. . ed an instance of a lesher band in a cotton. factory, which: ex- 
} hibited strong electrical: alieceregtien - 
C ese e examples show that leather ‘when subjected to “consid 
able friction yields an abundant supply of, electrici 
In the Proceedings of the American Philosophical Society for |. 
fees December, 1840, are mentioned several cases of individuals who 
b drew sparks of electricity from a coal stove, and from a common 
i a 
ss XXVIL Soe a new method of decomposing NSilicates in the 
pr acest of A nalysis ; by Henry Wurtz, of New York. 
Read being the ae Associaton for the De naam of pn at New 
ee August, 1 
, H avine had occasion in ee course a some researches u 
| ¥ the greensand of New Jersey, which will be presented to at 
Associat ation hereafter, to observe vi facility with which that sub- 
could be ee wens by hydrochloric acid. The use of 
chlorid of iain is however obviously attended with several 
inconveniences, such as its deliquescent properties, and the un- 
4 avoidable inteedaetiod of a large quantity of =" salts 
. into the solution, in the separation of the lime fr 
Chlorid of barium was therefore substituted, add the results of 
