Pound (mass) 6, 12, 18, 24, 32 and 42 pounds; 68-pounders also exist, and other nonstandard weapons use the same scheme. See carronade. A similar definition, using lead balls, exists for determining the gauge of shotguns. Pound (mass) The pound or pound-mass is a unit of mass used in the imperial, United States customary and other systems of measurement. Various definitions have been used; the most common today is the international avoirdupois pound, which is legally defined as exactly , and which is divided into 16 avoirdupois ounces. The international standard symbol for the avoirdupois pound is lb; an alternative symbol is
Canal pound called these "mule drinks", since the mules would drink from the water flowing over the towpath. Informal overflows were often replaced by a waste weir or lined with concrete or masonry to make a more "permanent" spillway. If the pound was many miles long, sometimes the canal would be designed with stop gates, so that if there was a break in the canal the whole pound would not lose all its water. Isolating the break would allow the company to make repairs sooner. For instance, on the 14 mile level of the Chesapeake and Ohio canal, there were stop gates