The Book of Household Management by Mrs. Beeton

the coldest as well as the hottest regions, although some species are restricted to particular countries, whilst others are widely dispersed. At certain seasons of the year, many of them change their abodes, and migrate to climates better adapted to their temperaments or modes of life, for a time, than those which they leave. Many of the birds of Britain, directed by an unerring instinct, take their departure from the island before the commencement of winter, and proceed to the more congenial warmth of Africa, to return with the next spring. The causes assigned by naturalists for this peculiarity are, either a deficiency of food, or the want of a secure asylum for the incubation and nourishment of their young. Their migrations are generally performed in large companies, and, in the day, they follow a leader, which is occasionally changed. During the night, many of the tribes send forth a continual cry, to keep themselves together; although one would think that the noise which must accompany their flight would be sufficient for that purpose. The flight of birds across the Mediterranean was noticed three thousand years ago, as we find it said in the book of Numbers, in the Scriptures, that "There went forth a wind from the Lord, and brought quails from the sea, and let them fall upon the camp, and a day's journey round about it, to the height of two cubits above the earth."