No doubt a sudden transference to an extreme climate is often prejudicial to man, as it is to most animals and plants; but there is every reason to believe that, if the migration occurs step by step, man can be acclimatized to almost any part of the earth's surface in comparatively few generations.
Amongst the most marked features of the change that has taken place since 1875 are the growth of religious and philanthropic establishments; the settlement of Jewish colonies from Bokhara, Yemen and Europe; the migration of Europeans, old Moslem families, and Jews from the city to the suburbs; the increased vegetation, due to the numerous gardens and improved methods of cultivation; the substitution of timber and red tiles for the vaulted stone roofs which were so characteristic of the old city; the striking want of beauty, grandeur, and harmony with their environment exhibited by most of the new buildings; and the introduction of wheeled transport, which, cutting into the soft limestone, has produced mud and dust to an extent previously unknown.
The credibility of the story of the migration from Sweden has been much discussed by modern authors.
The new synthesis reveals a universal decline from the 5th to the 10th centuries, while the Germanic races were learning the rudiments of culture, a decline that was deepened by each succeeding wave of migration, each tribal war of Franks or Saxons, and reached its climax in the disorders of the 9th and 10th centuries when the half-formed civilization of Christendom was forced to face the migration of the Northmen by sea, the raids of the Saracen upon the south and the onslaught of Hungarians and Sla y s upon the east.
Succinosuccinic ester behaves both as a ketone and as a phenol, thereby exhibiting desmotropy; assuming the ketone formula as indicating the constitution, then in Baeyer's equation we have a migration of a hydrogen atom, whereas to bring Ladenburg's formula into line, an oxygen atom must migrate.
Since the Euphrates valley has no mountains, En-lil would appear to be a god whose worship was carried into Babylonia by a wave of migration from a mountainous country - in all probability from Elam to the east.
To a certain extent they have passed under the same succession of influences; they have been subjected to the same invasions, and have received accessions to their populations from the same currents of migration or conquest.
Under external migration are comprised emigration and immigration, denoting simply direction from and to.
He has studied the folk-lore of those islands exhaustively, and from this source comes to the conclusion that the Polynesian migration from the Indian Archipelago may be approximately assigned to the close of the 1st or to the 2nd century.
From Russia, too, there is a stream of colonization across the Urals into western Siberia, and amongst the western Mediterranean populations there is constant migration to North Africa The greatest drain from Europe, however, has been across the sea to the United States, Canada and Australasia, especially to the first-named.