30 REPORT—1845. | 
On Recent Experiments on the Gas Voltaic Battery. By Professor Grove. 
No previous description of the gas battery having been communicated to the Asso- 
ciation, Prof. Grove entered into an explanation of the action of hydrogen gas upon 
spongy platina, and gave a description of the first gas battery constructed with pla- 
tina wire sealed into glass tubes in pairs,—hydrogen being’ put into one tube, and 
oxygen into the other. An arrangement of this kind being connected with a volta- 
meter, it was found that exactly the same quantity of gases was eliminated in the 
tubes of that instrument as combined in the tubes of the battery. Experiments have 
been made by Prof. Grove with a view of ascertaining if other gases might be used 
in the battery, and it was discovered that a great variety of gases might be so used ; 
and he then pointed out how perfectly any eudiometric analyses might be carried on 
with the gas battery, provided some attention was paid to a few sources of error. A 
form of the instrument as hitherto constructed by Prof. Grove was described, for 
the purpose of avoiding the absorption of atmospheric air by the fluid in the cells of 
the battery. A more recent construction of the battery was next described, in which 
many other applications of the voltaic battery are attained, being a combination in 
which several pairs of gas tubes are connected in one compact body. A main ad- 
vantage arising from this battery is the really constant condition of it; once charged, 
it appears that the action will go on for years, requiring nothing more than occasion- 
ally, at long intervals, adding a little zinc to the acidulated solution in one cell, for 
the purpose of supplying the loss of hydrogen in the tubes. The results of experi- 
ment have shown, that the most invariable action may be calculated on for years; 
and that, by this instrument, researches requiring for a long period the constant flow 
of a galvanic current may be most effectually carried out. Some experiments on the 
combination of phosphorus and sulphur with oxygen in the battery were then de- 
tailed; by which it was found that any inflammable body capable of volatilization 
gave a galvanic action with oxygen in the other tube. Camphor, alcohol, zther, 
and other bodies proved the generality of this effect. It was then stated, that 
throughout these researches it had been found that chemical action and voltaic action 
were convertible into each other. 
On the Voltaic Reduction of Alloys. By C. V. Watxer. 
This communication was intended to explain the methods by which the author has 
succeeded in throwing down metallic alloys from compound solutions by the action of 
galvanic electricity. The process adopted is to prepare a strong solution of cyanide 
of potassium, and commence electrolyzing it by means of a copper anode ; as soon as 
copper begins to be dissolved, the copper anode is removed, and its place supplied with 
one of zinc; after the action has continued for some little time, brass will be liberated 
on the cathode. The solution is now ready for use, and is operated upon by two or 
three Daniell’s cells, and with a brass anode. By similar means alloys of gold and 
copper, or gold and silver, may be deposited. The author reasons, that true brass is 
a definite chemical compound; and states, it appears possible that the anode, which 
is a brass of commerce, is a true alloy, plus an excess of zinc; that the solution it pro- 
duces is a mixed solution, which consists of the potassio-cyanide of brass and the po- 
tassio-cyanide of zinc. ‘This solution is very readily decomposable; it is therefore 
necessary to prepare it a short time previously to its use. Many specimens were exhi- 
bited of copper and other metals coated with brass. The author makes some remarks 
on the theory of the action; and concludes by stating that it will be quite possible to 
determine, within certain limits, the character of the alloy that shall present itself, 
and that we may be enabled to throw down gold and silver according to standard. 
Description of a Colossal Hydro-Electric Machine, mith a Notice of some 
Phenomena attending the production of Electricity by Steam. By W. G. 
ARMSTRONG. 
The machine described by the author, and which has recently been sent out to the 
United States of America, resembles the machine at the Polytechnic Institution in 
external dimensions, but is more powerful. ; 
As an illustration of the power of this machine, Mr, Armstrong stated that it had 
