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<\/p>\nThere is no such thing as a typical lock. Even on the same canal, each lock has some individuality and it\u2019s amazing the variety you\u2019ll encounter, but I\u2019ll try to imagine what a typical lock might look like while pointing out the differences you might find on various canals.<\/p>\n
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<\/a>\n\t\t\t<\/div>\n\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\tMost canals are narrow, meaning locks on that canal are just wide enough to accommodate (sometimes just barely) a seven-foot-wide narrowboat (most boats are about six feet, 10 inches wide). So we\u2019ll consider a narrow lock to be typical. Most narrow locks are just long enough for a 60- or 70-foot-long boat, but don\u2019t worry about this. Your boat hire won\u2019t rent a boat too long to fit in the locks of the canal(s) the boat hire serves.<\/p>\n On narrow locks, most likely the uphill gate will be a single gate with ground paddles on either side of the lock chamber. These paddles open and close underground sluices that let water from the pound (the stretch of water between locks) into the lock chamber. On a bog standard narrow lock, those paddles will be raised and lowered by rack and pinion gearing turned by a metal L-shaped windlass key or handle (provided with the boat). On some staircase locks, you might encounter hydraulically operated paddles with a housing resembling a tall, black-and-white fire hydrant, probably sitting at a jaunty angle.<\/p>\n Wide locks, of course, can accommodate boats wider than a standard narrowboat and usually can allow two narrowboats at a time to pass through. A single narrowboat in a wide lock unfortunately is a lot harder to control and of course it\u2019s not as economical in terms of water consumption. There\u2019s not really a hard and fast definition of how wide a wide lock is, but there\u2019s also no standard width for a wide beam barge. Typically wide beam barges are about 10 to 12 feet in width. Again, you\u2019re unlikely to be rented a barge too wide to pass through the locks on a particular canal.<\/p>\n The rear gate of a standard narrow lock will probably be two mitered gates with paddles in the gates, and the paddles will probably be raised\/lowered by rack and pinion gearing mounted to the balance beams that move the gates. Some gates with unusually heavy paddles will have hydraulic cylinders to raise\/lower paddles. These are still usually operated by a windlass key, but some locks will have permanently applied wheels to turn the hydraulics.<\/p>\n On some narrow locks, the downhill gate might be a single gate. All the locks on the South Stratford Canal have single gates. Every wide canal lock (to my knowledge) uses a pair of mitered gates at either end. I haven\u2019t encountered any, but I believe there are narrow locks with mitered gates on both uphill and downhill sides.<\/p>\nMitered vs flat<\/h5>\n
Ground paddles vs gate paddles<\/h5>\n