Though railroads are steadily superseding canals, there is still an immense amount of transportation done on the latter, and is donbtless destined to be done for a long time to come. Therefore, any improvements in canals are of great value. The invention which we here illustrate is a device for facilitating the entrance of boats into locks and their exit from them. When a boat enters a lock, it must of course displace water equal to the bulk of its submerged portion, and unless the boit moves very slowly indeed, this water has not time to run back through the narrow space between the sides of ths boat and the sides of the lock, but is piled up in front of the bow, retarding the movement of the boat. A similar difficulty is experienced in leaving the lock, and it is customary when a boat leaves a lock from the lowjr level, to open the gate, and let in a quantity of water at the stern to drive the boat out. This, of course, consumes the feed water, and is objectionable where the supply of water is limited. All of these difficulties are remedied by the simple plan represented in the annexed engraving. For the entrance or exit of the boat at the lower level, water ways or passages, a, are made on both sides of the lock, leading from the inner end of the lock directly outward through the wall, nd communicating with the water in the canal at the lower end of the lock. These passages are closed by gates, c, which are opened while a boat is entering or leaving the lock, but are closed while the lock is full of water or is being filled. While a boat is leaving a lock, as represented in the cut, the gate, c, being open, the water flows from the canal through the passage, 6, into the lock at the stern of the boat, and thus fills up the space vacated by the boat, and prevents the water from resisting the outward movement of the boat. On the other hand, while the boat is passing into the lock from the lower level, the water flows outward through the passage, n, thus preventing any piling up at the bow. A similar arrangement of the passage, 6, facilitates the entrance and exit of the boat into and ont of the upper level of the lock. It will be seen that the same plan is applicable to double locks. The inventor is making arrangements for the general introduction of this improvement during the next season. The patent for this invention was granted Nov. 6, 1860, and further information in relation to it may be obtained by addressing the inventor, James Davies, at Schuylkill Haven, Pa. THE space-penetrating power of the Rosse telescope surpasses the comprehensions of the human mind to apprehend in all its vastness. One astronomer remarks that the appearance of Jupiter, as presented in this wonderful instrnment, is as if a coach lamp were advanced into the tube ; and another declares that the sublimity of the spectacle afforded by Some of the large globular clusters of nebulas issnoh asti one can express.
This article was originally published with the title "Improvement in Canal Locks" in Scientific American 3, 25new, 385 (December 1860)