Weighing Locks. - The Locks for weighing boats in the vicinity of this village, are now completed and ready for operation. Their construction is founded upon the known principles of hydrostatics, that the whole weight of a body, which will float as fluid, is equal to as much of the fluid, as the immersed part of the body takes up, when it floats.
Two wooden locks are formed of equal dimensions, being 86 feet long, fifteen feet wide, and for feet deep, one above the other, in such a manner that one side of the upper lock extended down, forms also one side of the lower lock. The upper lock has gates of the usual form in lift locks, and connecting it with the canal on the same level, and the surface of the lower lock is on a level with the floor of the upper lock.
The boats are admitted into the upper lock, and the quantity of water displaced, or rather the increase of its volume is ascertained by measuring it, with a graduated scale in the upper lock drawing it off and finding the difference of measurement in the lower lock. The weight of a boat is then immediately determined by reference to a table calculated for the scale. Complete accuracy cannot be expected; but it will be sufficient for ordinary purposes. The time occupied in weighing a boat will probably not exceed twenty minutes. - Utica Sentinel.