when was the term leave no trace created
Leave No Trace In the mid 20th-century there was a cultural shift in wilderness ethics from woodcraft where wilderness travelers prided themselves on their ability to rely on the resources of wild lands to a post-WWII ethics of minimal impact on the environment.[2] Leave No Trace began in the 1960s and 1970s.[3] There was a large increase of wilderness visitation following the creation of new recreational equipment such as white gas stoves, synthetic tents, and sleeping pads. This began a commercial interest in outdoor recreation which in turn caused more visitors to national parks.[2] In those decades, the United States Forest Service, the Bureau of Land Management, and the National Park Service started to teach their non-motorized visitors how to have a minimal impact on the land. Wilderness Informational Specialists were trained to educate visitors on minimal impact camping in the different parks. In 1987 the three departments cooperatively developed a pamphlet titled "Leave No Trace Land Ethics".[4]
Dead end (street) The expression cul-de-sac comes from French, where it originally meant "bottom of the sack".[44] It was first used in English in anatomy (since 1738). It was used for dead-end streets since 1800 in English (since the 14th century in French).[45] The often heard erroneous folk etymology "arse/ass [buttocks] of the sack" is based on the modern meaning of cul in French, Catalan, and Occitan, but cul doesn't have that meaning in cul-de-sac, which is still used to refer to dead ends in modern French although the terms impasse and voie sans issue are more common in modern French.