1866. | Chemical Science. 529 
the shore end of the cable in Greenland is to be laid, indicate its 
security from ice when submerged. The landing places of the cable 
in Iceland are likewise in no way liable to be disturbed by ice of 
such a nature as to cause damage to the cable. In the discussion 
which followed, Mr. Holmes stated that the relay stations would pro- 
bably be mechanical, and not subject in any way to the human hand. 
Mr. Varley, referring to earth currents, was happy to inform the meet- 
ing that, although the earth currents in the present Atlantic Cable 
were decidedly strong, the speed of transmission was not retarded in 
the slightest degree. Captain Maury objected to the present system 
of making deep-sea cables, as rendering them unnecessarily heavy. 
Mr. Holmes, in reply to Captain Maury, said that he thought he 
might go so far as to say that in the deep-sea sections of the cable 
no iron would be used. 
Mr. Varley afterwards read a paper on certain phenomena which 
presented themselves in connection with the Atlantic Cable. These 
had reference almost entirely to certain phenomena of what he 
termed magneto-electric momentum, which were observed while 
testing the cable on board the Great Eastern, and also at Valentia 
after it was laid. The results, which were of the highest theoretical 
interest, will unfortunately not bear condensation. . 
In the Report of the Committee on the Transmission of Sound 
through water, it was stated that the rapid extinction of musical 
sounds in water rendered it almost hopeless to employ them for 
communicating signals in that medium, whilst an iron bar struck 
longitudinally could be heard at a very great distance. The Com- 
mittee are continuing their observations on the possibility of using 
these sounds as fog signals. 
A contribution by Mr. Evan Hopkins, “ On the Depolarization of 
Tron Ships,” was read. In this the author states that he has de- 
stroyed, or even reversed, in a few hours the polarization of vessels 
by means of electro-magnetic batteries. In order to test the prac- 
ticability of this system upon a ship of the largest size and containing 
an enormous mass of iron, the ship ‘ Northumberland’ was sub- 
mitted to this plan, and on the 4th of August it was depolarized 
head and stern in a few hours by means of two Grove’s batteries of 
five cells each and electro-magnets. be 
C0. 
CuemicaL Science. (Section B.) 
The proceedings of this Section were opened by Dr. H. Bence 
Jones, F.R.S., with an address, in which he specially referred to the 
relations of Medical and Chemical Science and the present system of 
Medical and Scientific Education. In the medical profession the early 
