The Great Lakes

Th' ofo.borate report on mo suivej tho greaWUke of tho West and Northwest by Maj. Gomstock, of the Engineers Department, is a vcry interesting document. The groet lakes havo a shore line of 5,000 miles, of wiiieh 4,800 have been surveyed by the Lake Suivey. The surleys of Lake St. Clair, Lake Huron, and Lake Superior are complated, although a Binall amount of work remains to be done to connect its triangulation with that of Lake Michigan. The survey of the shore Una and the hydrography of Great Britaia will be coiñpleted this summer. The survey. mi the St. Lawrence Eiver has heen cariietï from the north boundary of ïiêw York to liüko Ontario. There rejnaius to be sur-seyed Lake Champlain, oti whiéh the ooast survey is now at work, Lake Brie, and the Hfcgua Eiver. Tho report that the needs of commerce ou tho lakes are g-reator rather than less on tho ocean. are more frequent, vessels are always near the land, and charts are more neceesary. Tha lake tonnagein 1871 was 712,02.7 torn, ■ fully ialf as much as tho foreign tormage, .Mid ho hipping on the great lakes is au interest oí such magnitude as to roqnire eveíy advantnge that can be given to iti Tbe report alludcs to the great demand íor charts,. 0,000 bfting now issued every year. Measuralile tidüs havo been shown to exist in both Lake Mioliigan and Lake Buperior, and it is probable that they ■will be faund in Luke Iluron also, the peculiarity being that the tide waveH movo froiu orth to south, iustwid of froui oast to west.