pe 4p he Va 
TRANSACTIONS OF THE SECTIONS. 21 
The zincs not being folded at the bottom may be amalgamated by dipping them, 
first into acidulated water, then into a spare outer cell filled with mercury, and 
finally into their place in the battery. ‘The excess of mercury drains off, and will 
be found after the battery has been taken asunder. 
In dismounting the battery, the whole series of metals in each trough was with- 
drawn together by a frame, the essential parts of which are two parallel bars of 
wood, the interval between which can be adjusted, and which are somewhat longer 
than the trough. These bars are first to be separated sufficiently to enable the 
frame to be passed down over the S-connecting wires of the metals. The interval 
between the bars is then to be reduced, so that on raising the frame all the metals 
are carried with it, being supported by the projecting semicircular bends of the con- 
necting wires resting on the bars of the frame. Frame and all are to be immediately 
dipped into a tank of water, and the frame with its metals then laid aside to drain 
till the battery is again required. : 
The workmanship of this form of battery is throughout of the simplest description®. 
On Mr. Whitehouse’s Relay and Induction Coils in action on Short Circuit. 
By Professor W. Tuomson, LL.D., F.R.S. 
The peculiarities of Mr. Whitehouse’s induction coils, which fit them remarkably 
for the purpose for which they are adapted, as distinguished from the induction 
coils by which such brilliant effects of high intensity are obtained, were described. 
The chief part of the telegraphic receiving apparatus, the relay, was fully described, 
and was shown in action, through thirty yards of the Atlantic cable, after some re- 
marks explaining the general nature of a relay,—an electrical hair-trigger. The 
relation of Mr. Whitehouse’s relay to the Henley receiving instrument, was pointed 
out. The author expressed his conviction, that by using Mr. Whitehouse’s system 
of taking advantage of each motion for a single signal, instead of the to-and-fro 
motion, as in all systems hitherto practised, the Henley single needle instrument 
might be easily used, so as to give as great a speed on one line of wire alone, as is 
at present attained by two with the double needle instrument. ‘The beautiful method 
of reading by bells would be most ready and convenient for giving the indications to 
be interpreted as the messages, but the author believes that either by the eye or ear, 
messages may be read off with the rapidity and ease which will render the use of 
one telegraph wire in all respects-as satisfactory as that of two. 
On the Effects of Induction in long Submarine Lines of Telegraph. 
By Professsor W. Tuomson, LL.D., F.R.S. 
A general explanation of the theory was given, and the “law of squares”’ was 
proved to be rigorously true. It was pointed out, that when the resistances of the 
instruments employed to generate and to receive the electric current are consider- 
able in comparison with the resistance of the line, the observed phenomena do not 
fulfil the law of squares, because the conditions on which that law is founded are 
deviated from. The application of the theory to the alternate ‘positive’? and 
“‘negative”’ electrical actions used by Mr. Whitehouse for telegraphing was explained, 
and the circumstances which practically limit the speed of working were pointed 
out. Curves illustrating the enfeeblement of the current towards the remote end of 
the telegraph line, and the consequent necessity of the high pressure system intro- 
duced by Mr. Whitehouse, were shown. The embarrassment occasioned by the 
great electrical effect through the wire, which follows the commencement of a series 
of uniform signals with a full strength of electrical force, was illustrated in one dia- 
gram, which showed a succession of eight impulses following une another at equal 
intervals of time, and giving only one turn of the electrical tide at the remote end, 
or two motions of the relay, including the initial effect. The remedy suggested by 
* For many purposes to which a battery may be applied, it is convenient to be able to 
form a connexion directly with any required cell. In the battery exhibited to the Associa- 
tion, this was simply provided for by one end of each S-wire being allowed to project and 
turned up for a binding-screw to be soldered to it. 
