It will be seen by the annexed scrap that March is the fourth coldest month, or about midway between December and November. The same appears from the fifteen years’ observation at Mendon. (“American Almanac,” page 86.) The descent to extreme cold occupies seven months and is therefore more gradual (though a part of it is more rapid) than the ascent to extreme heat, which takes only five months . . . The three spring months, and also October and November, are transition months, in which the temperature rapidly changes.