so that a person not very observant of such matters would conclude that they had taken their last farewell; but then it may be seen in my diaries also that considerable flocks have discovered themselves again in the first week of November, and often on the fourth day of that month only for one day; and that not as if they were in actual migration, but playing about at their leisure and feeding calmly, as if no enterprise of moment at all agitated their spirits. And this was the case in the beginning of this very month; for on the 4th November, more than twenty house-martins, which, in appearance, had all departed about the 7th October, were seen again for that one morning only sporting between my fields and the Hanger, and feasting on insects which swarmed in that sheltered district. The preceding day was wet and blustering, but the 4th was dark, and mild, and soft, the wind at south-west, and the thermometer at 58½°; a pitch not common at that season of the year. Moreover, it may not be amiss to add in this place, that whenever the thermometer is above 50°, the bat comes flitting out in every autumnal and winter-month.
From all these circumstances laid together, it is obvious that torpid insects, reptiles, and quadrupeds, are awakened from their profoundest slumbers by a little untimely warmth; and therefore that nothing so much promotes its death-like stupor as a defect of heat. And farther, it is reasonable to suppose that two whole species, or at least many individuals of those two species of British hirundines do never leave this island at all, but partake of the same benumbed state; for we cannot suppose, that after a month's absence, house-martins can return from southern regions to appear for one morning in November, or that house-swallows should leave the districts of Asia to enjoy in March the transient summer of a couple of days.
