Fredericton, April
14, 1875
Sir
In my first letter addressed to you on this subject, many particulars
were necessarily omitted, explanatory of the system proposed to be
adopted, for raising the vessels to the level of the railway track; the
method of transportation; and the construction of the railway and
rolling stock.
It is now proposed to enter more largely into the outline of the
scheme, sufficient to justify the assertion of the feasibility of a
Ship Railway, and perhaps to satisfy the sceptical that it is quite
within the bounds of practicability.
It will be necessary to submit, in the course of this and succeeding
letters, the evidence upon which the conclusions have been based; and
it will be shewn that the scheme is an adaptation of well-known
principles and appliance actually in use - for other purposes, it is
true but the practicability of which has been fully demonstrated and
established beyond dispute.
It must be admitted, that if the transportation of vessels could be
easily, safely and quickly performed by means of a Ship Railway, it
would be desirable to adopt it in preference to a canal, on account of
its immense saving of cost, its comparative speed of transportation,
economy of maintenance, rapidity of execution; and freedom from the
influence of tide, mud, wind or frost.
It is here again asserted, without fear of contradiction from any
competent civil engineer, that a Railway can be constructed to answer
all requirements; that appliance can be adopted to raise vessels
steadily and easily, up from the sea level to that of a railway track;
and that rolling stock can be designed and made to convey them from
thence to any distance. Vessels can approach the terminus and be
lifted on to the Railway at all times of tide, day or night. A
half-tide canal can only be used six hours out of twelve.
Moreover, in the spring and fall, the season of navigation would be
opened earlier and closed later than it could possibly be in a
canal. There being no current in the latter, the ice would stay
as in a pond, until melted away in the spring. And in the fall it
would be frozen over before the navigation would close in the Gulf.
Thus for those precious few weeks at the close and beginning of the
season, means would be furnished for the rapid transmission of goods,
regardless of ice, wind or weather, whilst the canal would be
useless. Let us, therefore, calmly and without prejudice discuss
the feasibility of a Ship Railway, and judge whether we have or not
sufficient data to pronounce upon its practicability.
The largest vessel likely to ply between Montreal and St. John, or from
Quebec to Boston, would be a screw propeller of about 1,000 tons
burthen, which would weight with cargo and machinery about 2,000
tons.
The idea of raising a ship of this size out of the water might appear
chimerical, were it not of a daily occurrence, both by means of marine
railways and by the hydraulic lift.
Marine railways capable of carrying ships of 1,200 tons burthen, and
machinery capable of hauling them out of the water, may be seen any day
in Boston or Halifax.
The ship is first floated on to a cradle, which has been lowered in the
water to receive it, and when it is secured in position by blocks, it
is hauled up an incline by means of an endless chain and stationary
engine. If there is any room for wonder in this operation, it is
to wonder how such clumsy contrivances work at all, and then to wonder
how they can be made to pay.
Nevertheless, here is an example of what may be done, although very
inadequate for the purposes of a ship railway, such as is proposed for
Baie Verte.
In hydraulic lift graving docks, the ship is raised vertically out of
the water, having been first secured to a pontoon which sets on a stage
acting between columns ranged on each side in which are placed the
hydraulic rams. This pontoon is then raised, with the ship on it,
and upon arriving above the surface of the water, the valves in the
pontoon are opened and water let out, so that it can be floated off the
staging to any other place for repairs.
It is proposed to use this method of lifting at the terminus of the
ship railway in preference to that of a stationary engine with an
incline.
A few facts relating to the hydraulic lift erected in the Thames
graving docks, London, will be interesting, as forming conclusive
evidence of its practicability for the ship railway proposed.
The lift has been in operation upwards of ten years, and thousands of
vessels have been raised and lowered upon it without the slightest
accident. There are thirty-two columns ranged sixteen on each
side, which contain hydraulic presses capable of lifting 200 tons
each. The total lifting power is, therefore, 6,400 tons but
deducting dead weight, the net available power is 5,780. The
pumps are worked by a fifty horsepower engine, communicating with the
presses by an aperture of 1⅞ inch diameter. The raising and
complete docking of a vessel occupies about 25 minutes. The cost
of the lift, with all machinery, was 25,000 pounds sterling; that of
docking a vessel averages three pounds.
By dispensing with the pontoon, and substituting instead a cradle or
carriage on wheels (which rests on rails laid on the stage, between the
columns), there is an exact representation of what is proposed for each
terminus of a ship railway, with one exception, that the lifting force
will not require to be so great. It is said there would be a
great strain on the vessel when deprived of the support of the water,
and that in case of old vessels, they might fall to pieces. Your
correspondent does not see the force of this objections.
It is not proposed to carry rotten or unseaworthy ships. There
was not such result in the Thames Graving Docks, where old vessels are
obviously those requiring most repairs. The vessel would be
propped up at numerous points by keel, bilge and side blocks, adapted
to the vessel’s shape, immovable when once placed in position, and
therefore, supported as well as in the water. Certainly no vessel
would be subjected to the strain it is likely to encounter in a gale of
wind at sea.
In the next letter, the construction of the ship railway itself, as
well as the rolling stock, will be treated at length; likewise further
evidence in support of the scheme will be given.
I remain, Sir, your obedient servant,
H.G.C. Ketchum