The Life of Sir Rowland Hill and the

T85S-9] TUBULAR CONVEYANCE. 337
might be found one, too, less liable to interruption.
I called to mind an attempt made thirty or forty years
before by a Mr. Vallance, to propel a vehicle containing
passengers through a partially exhausted tube ; the
project then in view being the construction of an airtight
tunnel between London and Brighton. Of this
I had received some account from my friend, the late
Mr. Moses Ricardo, who had been a passenger in a
short experimental trip. He told me, indeed, that on
reaching the terminus he and those with him "got a
bang" by the abrupt stoppage of the vehicle, no
arrangement having been made for its gradual check ;
but knowing that such arrangement was very feasible,
and apprehending no severe consequences in any case
to letters or I newspapers, hoped a similar plan might
in hand. I therefore
prove applicable to the purpose
called in the assistance of two able engineers, viz., Mr.
Charles Hutton Gregory, and Mr. Edward Alfred
Cowper, who jointly made, with great care and skill, a
full investigation into the practicability of the scheme.
To avoid needless expense, they conducted their experiments
on a small scale, nor was any line of tubes of a
size for actual use ever laid down, though Mr. Cowper
devised and constructed a very ingenious air-pump,
especially applicable to the exhaustion of the tubes, as
was attested by its complete success. The conclusion
arrived at was that the plan was perfectly practicable,
but that for distances so short the economy in time
would not be sufficient to
justify the additional expense
involved in the innovation.
Some years later, remembering this ground of condemnation,
I inquired whether the plan could not be
made available for a larger purpose. Up to that time
it had not been found practicable to convey the mail
from London to Dublin, Glasgow, Edinburgh, or Paris,
VOL. n. z