THE EXHIBITION OP 1862. 
75 
a good working’ electric current — to have a perfectly insulated 
line of wire, which, by their united action, would supplant the 
letter-carrier and take the place of the Semaphore, equally 
regardless of tide, storm, or hazy weather. The labours of 
Bright, Walker, and Wheatstone have resulted in a degree of 
excellence which can scarcely be surpassed ; one has only to 
enter the nearest telegraph-office and have his message trans- 
mitted to the most distant county of England in a few moments, 
in order to be apprised of this fact. Further economy in the 
working, and still greater celerity, appear, however, to be the 
aim of the telegraph engineer. In one respect these endeavours 
must command our hveliest sympathy. The most simple 
system of train-signalling will assuredly be found to be the best 
not only in the working but in the less liability to get out of 
repair. Tyer exhibits an instrument which can be worked by 
the most unskilful hands, and by means of a gong, a bell, a red 
indicator and a black indicator, gives all the signals having- 
reference to the safety of the train, and cannot by any possi- 
bility be mistaken. One condition necessary to be observed, 
and which, if strictly adhered to, would prevent numerous 
accidents, is that “ no signal is to be considered complete until 
the reply has been received.” Allan exhibits his Automaton 
Telegraph, in which several novelties are introduced. In the 
first place, any person sending a message intended to be con- 
fidential, and having the cipher in his possession, punches the 
dots separately on a ribbon of paper at the signalling- office, 
and this paper being passed over the tooth of a small rotating 
spur wheel, electrical contact ensues at the different punctures, 
which is duly answered by a similar puncture on a similar ribbon 
of paper at the receiving office. By this method it will be seen 
that the signalling or recording clerk is no longer necessary, — 
the slips of paper are put into the machine at one office and are 
instantaneously reproduced on the paper at the other extremity. 
The punched hieroglyphics are delivered to the person for whom 
they are intended, and the telegraph clerk is completely igno- 
rant of the purport of the message. Both the positive and 
negative electric currents are used for marking, thus causing 
a saving of 30 per cent, in the number of currents sent through 
the wires. In Allan's composing-machine the Morse system 
of dots and dashes is altogether rejected, and the system of 
dots alone made use of — the number of dots forming any letter 
being punched on the ribbon at a single operation by merely 
touching one of the thirty keys of an instrument arranged like 
a piano. One of the particular advantages which the system 
possesses is that the ribbon of paper at the sending end may be 
passed through the apparatus several times, always reproducing 
a similar one at the receiving extremity, and may thus be a 
