RECAPITULATION.

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that begin first to blow west of the Mississippi, move slowerin autumn, the hurricanes of the West India Islands mightbe anticipated by telegraph, when the cold winds are observed' in the west, for they appear to be developed under conditionssimilar to those of the winter storms.

The long line of low barometer, with its attendant atmo-spheric disturbances, is often, no doubt, propagated from westto east, during winter, across the Atlantic to Europe.

At the present moment we have no means of anticipat-ing the approach of some of the winter storms of Britain,beyond twelve hours before they burst upon our coasts; butas soon as the telegraph is laid down across the Atlantic, it isprobable that the sudden irruptions of our high winds inwinter may be known for three days or more before theyoccur.

Such, then, is an outline of the more important featuresof the climate of North America. I have endeavoured togive my explanation of certain well-marked phenomena asconcisely and as clearly as possible. These views furtherobservation and reflection may lead me to modify; butwhatever may be the change in this respect, I shall alwaysretain a lively and constant impression of the kindness, thehospitality, and the liberality which I experienced, in thecourse of my researches, from the American men of sciencewho have devoted attention to this branch of study.

The meteorological observations which enabled me toexamine into the climate of North America were, throughthe politeness of Dr. Henry, obtained from the Registers ofthe Smithsonian Institution. A few were obtained from theregisters kept at the military forts, and on the next page aregiven those relating Jo the weather from 9th to 14th No-vember 1854.