Liverpool, and act as signaller, while he was to stay in New York,
receive the information, and buy or sell in accordance with it.

"Our apparatus was very simple. At each terminus of our line, so to
speak, we had a room, inaccessible save to ourselves. These rooms,
darkened, and carefully kept at a fixed temperature, contained nothing,
save, in one corner of each, a chronometer regulated with precision,
and, in opposite corners, a set of boxes, containing each a snail. At
the signalling end, at a fixed hour, which the chronometer gives with
the greatest accuracy, and when I know that my partner, by agreement,
will be present at the other end to receive intelligence, I go into my
room, informed as to the condition of the Liverpool market, and prepared
to transmit particulars of the same to him. Here are two boxes, divided
into three compartments each, and a _male_ snail in each compartment.
If flour is down, offering a chance for profit in New York upon 'time'
sales, I approach the box marked _minus_, the three snails of which are
called _x_, _y_, and _z_. I take up a little tube,--such a one as is
used by chemists to drop infinitesimal portions of any liquid; I dip
this into a vial marked _No_. 1, containing a solution of salt in
water,--there is a row of these vials, the solution in each being of a
different strength,--and then, with the moistened tube, I touch snail
_x_, or snail _y_, or snail _z_, or any two of them, or all three, once,
twice, three times, or repeatedly, according to the news I wish to
signal,--noting the effect of the poison, and recording the particulars
in a book kept for the purpose,--recording them with a nicety of
intelligent discrimination such as can be obtained only by long and
practised observation. I send an abstract of this record by every mail
to my partner, so as to verify our results and to detect immediately any
derangement. At _his_ end of our line the brave John Meavy waits before
two similar boxes, in each compartment of which is a _female_ snail. He
is a skilled observer, and his quick eve beholds snails _a_, _b_, _c_
exactly (through sympathy) _repeating_ the effects I am producing in
_x_, _y_, _z_,--though the distance between them is over three thousand
miles! He knows the meaning of these slight effects, and, going upon
'Change, buys or sells with a perfect assurance of profit.

"Such was my telegraph, in its rudest outline; but I had systematized it
to a degree of far greate