Cutbush on the Voltaic Lamp. 333 
Philosophy, vol. 2, page 93, American edition. Since the 
original was contrived by Mr. Volta, aided by Dr. Ingen- 
houz, several very important improvements have been 
made—more especially that arrangement by which is 
formed in the bottle extemporaneously, and of course with- 
e use of an additional bottle and syphon, or the pre- 
vious filling of bladders with hydrogen gas, a mode heretor 
fore adopted both by Volta and Ingenhouz. In the appa- 
ratus which [ procured, before it was altered I was obliged 
to fill the bottle with water, remove the stop cock and its 
connexion with the string from the electrophorus, and adapt 
a syphon coming from a bottle or flask containing dilute 
sulphuric acid and iron or zinc filings; and when filled 
with gas, to pour water into the upper vessel, in order to 
ferce it out when the cock was turned, which causes by its 
connexion with the plate of the electrophorus the transmis~ 
sion of the electric fluid, and of course its passage between 
the two conducting points. Filling the gas bottle in this 
way with gas, is at all times attended with trouble. Not 
possessing one of the improved kind, which obviates this 
mconvenience, I thought of having mine altered, which I 
had done, and found it to answer the purpose. The alter- 
ation consisted in removing a brass tube, which went from 
the lower to the upper vessel, and substituting in its place 
a glass one, which was attached and cemented to the 
upper vessel, so that when it was inserted in the bottle, and 
the upper screwed to the lower vessel, it would occupy 
such a distance as to be equivalent to the capacity of the 
water holder, a circumstance necessary to be attended to, 
in order to prevent the fluid when the gas is generated in 
the bottle from running over. It is obvious, therefore, that 
according to this improvement, all that is necessary 1s 40 fill 
the bottle with a mixture of sulphuric acid and water, in 
the proportion of about one of the former to eight of the 
latter, and throw in as occasion requires through the tube, 
when the upper is screwed to the lower vessel, either zinc 
or iron filings. ‘The gas, as it is generated, will cause the 
fluid to rise in the tube into the upper vessel, which is al- 
ways ready by its pressure, when the cock is turned, to 
force it through the aperture so as to come in contact with. 
the spark. The bottle containing the diluted acid will last 
many months without being renewed, and when the satura- 
Vo. IT.....No. 2. 43 
teeern 
