March 16, 1882} 
from a special fund subscribed by the members of the expedi- 
tion, and amounting to 10,000/. 
Wir the beginning of the present year the Geographical 
Society of Paris have begun to issue a fortnightly Compe Rendu 
of their proceedings, published within ten days after their 
meetings, A quarterly volume will also be issued containing 
memoirs and other papers of some length. ‘This is a great im- 
provement on the old Budletin, which was often months behind 
date. The Society now numbers upwards of 2150 members. 
WE may remind our readers that Mr. Edmund O’Donovan, 
so well known as the Daily Mews correspondent in the Trans- 
Caspian region, and more particularly at Merv, will read a paper 
before the Geographical Society, on March 27, on the geography 
of Mery and the surrounding country. The meeting will, we 
believe, ke held as usual in the theatre of London University, 
at Burlington House. 
AT the last meeting of the Geographical Society of Paris, M. 
Achille Raffray, Vice-Consul at Massowah, read an interesting 
paper on his journey in Abyssinia, and in the country of the 
Raya Gallas. It was announced during the evening, that one of 
the Society’s gold medals had been awarded to M. G. Revoil, 
for his journeys in Somali-land, and another to Dr. Lenz, for 
his recent journey to Timbuktoo, the Logerdt prize mecal to Dr. 
Montano, for his explorations in the Malayan Archipelago, and 
the new Jomard prize to Prof. Gaffarel, for his services in the 
cause of historical geography. 
DirEcT news from Lieut. Bove, the leader of the Italian 
Antarctic expedition which started from Buenos Ayres, has been 
received in Italy. The expedition was most hospitably received 
at Buenos Ayres. The Government of the Argentine Republic 
has sent out a commission with the Italian Expedition for the 
purpose of carefully revising the survey of the coast of their 
country ; thus the expedition now consists of four ships, viz. 
Santa Cruz, Uruguay, Cape Horn, and a steam barque. The 
Cape Horn is the largest vessel, and will proceed to the Antarctic 
regions, while the -C7zgway will remain at Cape Horn. The 
Santa Cruz will attend to the coast survey. The expedition 
started on November 8, and Lieut. Bove hoped to leave Cape 
Horn by the end of December in order to sail across to South 
Shetland and Grahamsland. He hoped to be back at Tierra del 
Fuego by the end of March, to stay there till May, and then to 
leave for Buenos Ayres. 
ON THE ELECTROLYSIS OF SULPHATE OF 
COPPER? 
-~HE immediate object of this research was to examine 
various conditions connected with the transmission of 
electric currents through solutions of salts of copper, and to 
ascertain the influence of those conditions on the electro-chemical 
equivalent of copper, also to observe for any signs of conduction 
of electric currents by such liquids without electrolysis. In 
many of the experiments some difficulty was experienced in 
ascertaining the exact loss of weight of the anode, in conse- 
quence of finely-divided copper falling from it, The powder 
which fell off, exposing as it did a large surface to the liquid, 
was somewhat oxidised, and also in acid solutions freely dis- 
solved, and its true weight, and therefore the exact loss of the 
anode could not be found. 
Amongst the results obtained were the following :—that a 
porous partition in a solution of sulphate of copper affected the 
deposit only by preventing the products set free at the two elec- 
trodes becoming mixed together; a large surface of cathode 
diminished the amount of deposited metal, by allowing more 
copper to be re-dissolved by ordinary chemical action; the 
effect of diluting the liquid with sulphuric acid was to slightly 
diminish the amount of deposited copper; diluting the solution 
either with water, glycerine, propionic acid, solution of sulphate 
of sodium, borax, boracic acid, or of ammonie alum, had very 
little effect (and that variable) upon the amount of deposit ; 
much less copper is dep sited per unit of current in a hot liquid 
than ina cold one ; without the influence of an electric current, 
a copper plate dissolved fifty-six times faster in an ordinary 
depositing solution of sulphate of copper at 180° F. than at 
50 F.; the amount of copper deposited by aid of a current in 
such a liquid at 50° F, was about 18 per cent. greater than at 
* Abstract of a paper read before the Birmingham Philosophical Society, 
January 26, 1882, By G. Gore, LL.D., F.R.S. 
NAL Oi 
473 
180° F, ; with an electric current of small density, and a suffi- 
ciently corrosive liquid containing a very small amount of dis- 
solved copper, no deposition of copper takes place; instead of 
an electric current protecting a copper cathode from chemical 
corrosion, it indirectly increases that corrosion ; a sufficient rise 
of temperature (viz. from 50 F. to 180° F.) was nearly twice as 
influential as the electric current in increasing purely chemical 
corrosion ; the purely chemical corrosion of a copper anode 
in ordinary sulphate of copper-depositing solution, is less 
than that of a separate piece of copper without a current; 
the loss of the anode is greater than the gain of the cathode in 
nearly every instance, and this difference is slightly greater with 
near electrodes than with distant ones ; reduction of temperature 
is a most influential circumstance in diminishing the chemical 
corrosion of the two electrodes, and making their alterations of 
weight, by electrolytic action, approximate to each other ; purely 
chemical corrosion of the copper is not entirely prevented by 
using a pure and cold solution not containing any free acid ; the 
inequalities of loss and gain of the two electrodes are largely, if 
not wholly, due to purely chemical action ; there exist relative 
degrees of chemical corrosive power and strength of current, at 
which the influence of the two are equal, and a copper cathode 
neither dissolves nor receives a deposit in an acidulated solution 
of sulphate of copper containing a very small an ount of dissulved 
copper salt; the amount of copper deposited is not sensibly 
affected by the presence of a small amount of green sulphate of 
iron in the solution ; nor by the exposure of such a solution 
freely to the air or to the light ; differences of relative position 
of the electrodes to each other affect slightly both the amount of 
total loss of the anode per unit of current, and also the relative 
amount of such loss to the amount of gain of the cathode; the 
presence of a considerable quantity of persulphate of iron in the 
solution affects perceptibly the amount of deposited copper, but 
that of a moderate proportion of nitrate of copper in the solution 
had no conspicuous effect of the kind ; the chemical corrosion of 
sheets of copper in pure acidulated solution of sulphate of copper 
was not directly proportionate to their amount of surface, but 
was relatively less upon the larger surface ; the amount of copper 
deposited per unit of current did not vary much with the magni- 
tude of the cathode or the density of the current ; a very feeble 
thermo-electric current caused a cold copper anode to lose a 
little more, and a hot cathode to lose slightly less, than without 
the current ; stirring the solution increased slightly the loss of 
weight of the anode per unit of current, and diminished to a 
small extent the gain of the cathode ; stirring a pure acidulated 
solution of sulphate of copper increased the proportion of loss of 
weight of copper by ordinary chemical corrosion without an 
electric current from "07 grain to ‘17 grain, or from "411 to I’o, 
but in a less proportion if a current was entering the copper asa 
cathode ; a considerable degree of density of current appears to 
be favourable to enabling a nearer approximation to be made to 
the true electro-chemical equivalent in the weight obtained of 
deposited copper. 
Many of the experiments indicate, and the whole of them are 
consistent with the general inference, that in nearly all cases of 
electrolysis, the two forces, ordinary chemical and electro- 
chemical, coexist and operate independently at the same surfaces 
of liquid and metal; that ordinary chemical action, both ot 
simple oxidation and of corrosion of both electrodes by free acid, 
takes place in all cases, and is a phenomenon essentially distinct 
from, and independent of, electro-chemical corrosion of the 
anode, and deposition upon the cathode. The two classes of 
phenomena, however, are coincident, and affect each other in 
various indirect and secondary ways. 
In consequeace of these two actions being essentially distinct 
and independent of each other, an electric current passing out 
of a piece of copper into an acid solution does not directly in- 
crease the rapidity of ordinary chemical corrosion of the metal, 
nor does a current entering from such a liquid into a copper 
cathode, protect in all cases that metal from such corrosion. 
Some of the experiments show that stirring the liquid increases 
the ordinary chemical corrosion both of the anode and of the 
cathode, and therefore that the technical process of swaying to 
and fro by mechanical means, articles which are being plated in 
a depositing solution, tends to corrode them. 
That temperature also greatly influences the chemical corrosion 
is proved by the numerical results. The higher the temperature 
the greater was the amount of chemical solution of the hot 
copper without current, and of the hot electrodes ; and for equal 
rise of temperature, the increase of corrosion appeared to be 
