The height of these mountains has been a subject of much dispute. A scientific gentleman, whose remarks on physical subjects merit consideration and respect, supposes the summit of Mount Washington to be about seven thousand eight hundred feet above the level of the ocean; seventy-two feet below the point, which, in the latitude of 44° 15´ (that of these mountains) is the estimated point of perpetual congelation on the eastern continent. This point, he says, from the greater coldness of the American climate, cannot exceed, but must rather fall short, of what it is in the European climate. The climates of America are indeed colder than those of Europe in the same latitude during the winter, but in the summer they are generally much hotter. Nor are the mountains in any part of New England of sufficient height and extent to lessen materially the degree of heat generally prevailing. The air on the summit of Mount Washington, therefore, must continually be rendered less cold by the ascent of the intensely heated atmosphere from the subjacent regions. As the whole country partakes of this heat, the ascending volume, whencesoever derived, must be heated to nearly the same temperature. It seems scarcely credible, therefore, that the temperature of the atmosphere around the single point of Mount Washington should not, during the summer, be sensibly raised by the general heat of the country: for we are to remember that this is the only height in the United States which approximates near to the region of perpetual frost. The following observations of Dr. Cutler exhibit the state of vegetation on these mountains:— “At the base of the summit of Mount Washington, the limits of vegetation may with propriety be fixed. There are indeed, on some of the rocks, even to their apices, scattered specks of a mossy appearance; but I conceive them to be extraneous substances accidentally adhering to the rocks, for I could not discover, with my botanical microscope, any part of that plant regularly formed. The limits of vegetation at the base of this summit are as well defined as that between the woods and the bald and mossy part. So striking is the appearance, that, at a considerable distance, the mind is impressed with the idea that vegetation extends no farther than a line, as well defined as the penumbra and shadow in a lunar eclipse. The stones that I have by me from the summit have not the smallest appearance of moss upon them. “There is evidently the appearance of three zones—the woods, the bald, mossy part, and the part above vegetation. The same appearance has been observed on the Alps, and all other high mountains.