Tho memorial of tbe Ch nrtiber of Commereo in Ibis city in relation to lake defenees has been uid Isefore the legislature,' accompanied by a letter frorn Captain Ericsson. In order to show Ihat vessels like the Monitor can pasa through locka twenty-flvo feet broad and two bundn d feet long, the uornmittee givo the f'ollowing letter from Captain Ericsson. " New York, April 14, 1862. "Sm: Altera full consideration of the subject of yoür inquiiy, I have to state that an injpregnubly -iron vespel, two hiindred feet long ;tnd tweuty-Iive j feet witl?, oonstruuted on tho general plan of the ' Monitor,' wül havu suffi cient buoyancv to earry a éhot-proof iron turret carrying a gun of fifteen-inch calibre, with a buil of four huncired niid lilty ponnds, and papable of destroying any hostile vesíel that could be pnt on the fakes. "Without coal. ammunition and stores, such a vesse) will draw six feet b:x inches, and measure eiglr.een feet in height from bottom of keel to top of turret. Before going into action a certain qunntity of ballast, in addition to coal, ammunition nnc' stores, wil! bo pnt on board, in order to attain wbat may be tenned the fighting draft of eight feet. " Yours, very respectfully, J. EniCHSON, ': Hoa. s. Iï. Rugóles. Chairman of Lake Defence Committee, N. Y. Chainber of Coinmerce. " P. S. - Tho cost of a war vesse!, ns abovo suggested, will not exceed OoO.