Symbols representingthese valves provide awealth of information about the valve it represents. Symbols show the meth-ods of actuation, the number of positions, the flow paths and the number of ports. Hereisabriefbreakdown of how to read asymbol: Every symbol has three parts (see figuretoright).
Description. Safe Harbor Dam is a dam located just 5.7 miles from Millersville, in Lancaster County, in the state of Pennsylvania, United States, near Lockport, PA.escription. Safe Harbor Dam is a dam located just 5.7 miles from Millersville, in Lancaster County, in the state of Pennsylvania, United States, near Lockport, PA.
Pearl Harbor, a naval base on the southern coast of Oahu Island, Hawaii, is the headquarters for the U.S. Pacific Fleet. Ford Island, pictured here on Nov. 10, 1941, lies at the center. In 1941, it would become an important target for the Japanese.