You are looking to the south over the Gatun Locks toward Gatun Lake. The locks are built in three flights. This is the upper flight you see. In going through the three locks a vessel is lowered, or raised, 85 feet. At the same time it travels ahead seven-tenths of a mile. All the locks in the Panama Canal are built in pairs, as is shown in the view. So the three flights of locks at Gatun mean six locks. If one lock is out of repair, the other can be used. Or two ships can be lifted or lowered at one time. Or one ship can be going up while another is going down. The side walls of the Gatun Locks are 81 feet high, from 45 to 50 feet wide at the bottom, and 8 feet thick at the top. From one side to the other they measure 300 feet. Each lock is 1,000 feet long and 110 feet wide. They are built of concrete. You will observe the two gates in the lock. If one is broken the other will hold the water, so there will be no delay to the shipping. There is also an extra dam which you can see at the left end of the left lock. It can be shut in case of an accident in the locks. It is therefore called the emergency dam. It is closed in this view which was taken while traffic was halted. In front of the gates there are heavy chains to keep ships from ramming the gates. Gatun Lake, in the background, has been largely made by the Gatun Dam. This dam is 1½ miles long, ½ mile wide at its base, and 115 feet high at its highest point. The channel of the Canal is in the lake for some 15 miles, and is there 1,000 feet wide and reaches a depth of 85 feet. The water thus penned up is partially used to flood the locks. A spillway has been built to let the surplus water escape from the lake to the ocean. Keystone ID: 21784 Note: All titles, descriptions, and location coordinates are from the original Keystone Slide documentation as supplied by the Keystone View Company. No text has been edited or changed.