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182 -'THOMPSON'S COAST PILOT. 5th. Northeasterly storms.--The barometer falls previously from tour to eight-tenths of an inch, varying in time from one to four hours, and continues falling until the storm arrives at its crisis, when the barometer begins to rise and continues ris- ing until that part of the storm which comes from the NW passes off. 1) us 6th. Southerly storms.--The barometer falls previously from one to four-tenths of an inch, varying in time from six to twelve hours. These storms generaliy precede unsettled weather; at such times the barometer continues low, and very slight additional depressions are followed by rain. A southerly storm is perhaps the most difficult to judge of by appearances, as appearances change so frequently without any real change in the atmosphere. During this class of storms, the utmost confidence should be placed .in the barometer. After the first indication as above, and the barometer does not rise, but remains stationary, it is strong indication that the storm has not all passed. The foregoing rules are the result of long and careful obser- vation. It must be remembered that storms occur under different circumstances in different parts of the globe, yet, tak- ing the first three of the above rules as a basis of calculation, a short experience, with the exercise of the judgment, will enable one to determine very correctly concerning approaching changes in the weather. | A LUNAR TIDAL WAVEIN THE NORTH AMERICAN LAKES. Extract from a paper read by Lieut.-Col. Graham, before the American Association for the Advancement of Science, August, 1860. "Much has been written at various periods, on the fluctua- tions in the elevation of the surface waters of the great fresh water lakes of North America. Valuable and interesting memoirs have appeared from time to time in the American Journal of Science and Arts, published monthly at New Haven, | Connecticut, within the last thirty years, on this subject, writ- ten by the late Brevet Brigadier-General Henry Whiting, of