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 been briefly outlined, and, although they are subject to considerable variation as to temperature, velocity, and limits, in response to the varying forces that act upon them, this general view must suffice for the present purpose.

Now to consider for a moment some of the phenomena resulting from the presence and relative positions of these ocean currents, so far as such phenomena bear upon the great storm now under consideration. With the Pilot Chart of the North Atlantic Ocean for March there was issued a Supplement descriptive of water-spouts off the Atlantic coast of the United States during January and February. Additional interest and importance have been given to the facts, there grouped together and published, by their evident bearing upon the conditions that gave rise to the tremendous increase of violence attendant upon the approach of this trough of low barometer toward the coast. In it were given descriptions, in greater or less detail, of as many as forty waterspouts reported by masters of vessels during these two months, at various positions off the coast, from the northern coast of Cuba to the Grand banks; and since that Supplement was published many other similar reports have been received. Moreover, it was pointed out that the conditions that gave rise to such remarkable and dangerous phenomena are due to the interaction between the warm moist air overhanging the Gulf stream and the cold dry air brought over it by northwesterly winds from the coast, and from over the cold inshore current, and the greater the differences of temperature and moisture, the greater the resulting energy of action. Reports were also quoted showing that the Gulf Stream was beginning to re-assert itself after a period of comparative quiescence during the winter months, and with increasing strength and volume was approaching its northern limits, as the sun moved north in declination.

Such, then, were the meteorological conditions off the coast, awaiting the attack of the advance guard of this long line of cold northwesterly gales,—conditions still further intensified by the freshening gale that sprung up from the southeast at its approach, drawing re-enforcements of warm, moist ocean air from far down within the tropics. The energy developed when storm systems of only ordinary character and severity reach the Atlantic on their eastward march toward northern Europe is well-known, and need not be referred to further: let us now return to the consideration of this storm which is advancing toward the coast at the