THE LIFE OF MAN IN THE TEMPERATE ZONES 272 Climate and man in the temperate zones: general— Northward movement of civilisation in the north temperate zone—Present-day migrations within the temperate zones—The continents and the temperate zone —Differences between northerners and southerners —Variety of conditions in the temperate zones: classification—Life of man in the forests of the temperate zone—Forest clearings—The steppes—Climates and crops in the temperate zones—The deserts—Mountains —Climate and weather: some mental effects—Climate and weather and military operations—Railroads—Transportation by water—Various effects of the weather.