Home › L › Laurens (JOHN an American military)

Laurens (JOHN an American military)

JOHN, an American military officer; son of the preceding; born in South Carolina in 1754. After receiving his education in England he Joined the American Continental Army In 1777, becoming aide-de-camp and secretary to Washington. Laurens so highly listinguished himself in the battles of LAURIER Germantown and Monmouth, and in other operations as to earn the title of the "Bayard of the Revolution." In 1780 he was sent to France to negotiate a loan. He was killed in action at the Combahee river, S. C., Aug. 27, 1782.

GROUP, LAURENTIAN a vast series of rocks, 30,000 feet in thickness, and covering an area of at least 200,000 square miles N. of the St. Lawrence river. It is lower, and consequently older, than the Cambrian. It consists of an immense series of crystalline rocks, gneiss, micaschist, quartzite, and limestone. It is divided into Upper and Lower Laurentian. The Upper, more than 10,000 feet thick, consists of stratified crystalline rocks. It mainly consists of felspars. The Lower Laurentian, about 20,000 feet in thickness, is unconformable with the Upper. It consists mainly of a reddish gneiss, with orthoclase felspar; interstratified with thin hornblendic and micaceous schists, with beds of usually crystalline origin, and others of plumbago. The Laurentian volcanic rocks of Ottawa, Argenteuil, etc., in Canada, consist of finegrained dark greenstone or dolerite. a LAURENTIAN MOUNTAINS, range in Canada extending for over 3,000 miles from Labrador to the Arctic Ocean, forming the watershed between Hudson Bay, the St. Lawrence, and the Great Lakes, and dividing the same bay from of the Mackenzie river. the Some of the peaks attain a height of 4,000 feet. The rock formation belongs to the fundamental metamorphosed sedimentary deposits known as the Laurentian system. sources