40 HEIGHT OF THE GREATEST OR SPRING TIDES IN 1831. The unit of altitude of any place, multiplied by the quantities in the above table, will give the height of the spring tides at that place, in the present year. The unit of altitude at Boston, Salem, Marblehead, Cape Ann, and Plymouth, is 114 feet: At New York, St. Augustine, Block Island, Elizabeth Town Point, Florida Keys, Elizabeth Islands, Hillsborough Inlet, Nantucket Shoals and Town, Buzzard's Bay, Martha's Vineyard, Long Island Sound, Rhode Island, and Sandy Hook, 5 feet: At Charleston, S. C., Monomoy Point, Port Hood, Prince Edward's Islands, St. Simon's Bar, and St. Simon's Sound, 6 feet. These, multiplied by the preceding numbers, give for the height of the greatest tides, this year, in those places. Tide of Boston, N. York, Charleston, &c. &c. ft. in. ft. in. &c. 5 3 4 26 9 1 4 4 10 4 10 8 4 5 8 24 10 4 4 7 5 66 26 By the preceding Table it appears, that the tides of March 15th, April 13th, May 13th, September 23d, October 22d, November 20th, and December 20th, will be the most considerable in 1831. The height of the tides, however, depends so much on the strength and direction of the wind, that it not unfrequently happens that a tide, which would independently of this have been small, is higher than one otherwise much greater. But when it happens that a tide, which arrives when the Sun and Moon are in a favorable position for producing a great elevation of the sea, is still further increased by a very strong wind, the rise of the water will be uncommonly great, and injury and loss probably thereby occasioned. A remarkable instance of this occurred in Boston and generally along the coast of New England, on the 26th of March last, when the tide, in itself one of the three highest in the year, being further elevated by a violent easterly gale, actually rose 16 feet 5 inches, and caused very considerable damage. This tide was the greatest observed in that city within the last 45 years. The following Table contains the unit of altitude of several ports and places on the American coast, from the best authorities. The height of the tides in the Bay of Fundy was ascertained by recent observations. Advocate Harbour (Bay of Fundy) 50 Bay, Buzzard's The following Table contains the difference between the time of high water at Boston, and at a large number of places on the American coast, from which the time at any of them may be easily ascertained, by subtracting the difference at the place in question from the time at Boston, when the the sign is prefixed to it, and by adding it, when the sign is +. The time of high water, in the calendar pages, is of that tide immediately preceding the southing of the moon. Albany Andrews, St. Augustine, St. Annapolis Bay, Bristed |