PNEUMATIC LOCKS IN OPERATION.
The canal lock of to-day is a very slow working affair, as we all know, and is such a clumsy piece of mechanism that only ships of a limited tonnage can pass through it. When a canal-boat comes along it is let into the first lock, and if that is on the higher level the gates are closed, and the water is allowed to run out until the boat is floating on a level equal to that in the other portion of the lock. Then the gates are opened, and the boat passes on. If it is necessary, on the other hand, to raise the vessel from the lower to the higher level, much more time has to be consumed in order to pump the lock full of water.
By Mr. Dutton's method, however, the vessel comes along the canal, and it may be as large a ship as an ocean freighter, and it may carry as great a cargo as 12,000 tons, and yet it can slip into one of the great steel tanks 510 feet long, and a boy can open the compressed-air valve, and let the great ship travel gently down the elevator shaft until it reaches the lower level of the canal. The operation requires perhaps fifteen minutes, instead of hours; and no more time is necessary for ships of equal tonnage going in the other direction, since a much greater weight of water can be run into the upper tank from the higher level of the canal than could be counterbalanced by any kind of steamship that would need to be lifted from the lower level.
A company has been organized to build a canal from the Atlantic to the Great Lakes, and it is its intention to use Mr. Dutton's locks along the way; not more than two or three will be necessary. But as it will cost about one hundred million dollars to carry out the enterprise, it may be some years before they will be able actually to begin work.
It is the belief of those interested in the construction of this great canal that there is no economy in cheap construction. Good results may only be obtained by good work. The Suez Canal, for example, is cheaply constructed; it is only 72 feet wide at the bottom, and large ships may pass one another only when one goes into a sort of siding, where it usually runs aground. The expense of getting ships out of the sand, since the traffic was first opened through the canal, has far surpassed the sum for which the canal could have been constructed so as to avoid such delays and accidents. Therefore it is proposed that any maritime canal to be built should be fully 250 feet wide, and 30 feet deep at least.
One of the great undertakings which would be connected with the construction of such a canal would be the reversion of the current of Lake Champlain, in order to deepen the water in the upper Hudson. This would be done by diverting a portion of the waters of the St. Lawrence River into Lake Champlain, and such a condition of affairs would develop at Waterford an immense water-power, nearly equal to one-third that of Niagara Falls. This water-power could be used for developing electric-power, and the canal could be illuminated with electric-light at night so as to make traffic almost as easy in the dark hours as in the daytime.
The effects of such an enterprise would be far-reaching. An open-water route from the Atlantic to Buffalo, Cleveland, Detroit, Chicago, and Milwaukee would make those great inland cities practically seaports, and therefore the people who live in those cities would be able to purchase all sorts of commodities more cheaply than they can now, because the charges of transportation by water directly from foreign countries would be much cheaper than it is now, when there has to be a transshipment of the goods on the coast, and transportation by rail, which is expensive. On the other hand, the people of those other cities would also be able to sell more of their own products, and to greater advantage to themselves, because they could deliver them in foreign countries more cheaply than they can now.