The idea conveyed by the expression necessaries of life is, within certain limits, a relative one. In warm countries, a workman's family needs less clothing, shelter, fuel and even food[162-1] than in cold countries. This difference becomes still more striking when the warm countries possess absolutely cheaper food as, for instance, rice, Turkish wheat, bananas etc. Here, evidently, other circumstances being the same, the rate of wages may be lower.[162-2] The cultivation of the potato has operated in the same direction; since an acre of land planted with potatoes yields, on an average, twice as much food as the same acre planted with rye.[162-3] In France, two-thirds of the population lived almost without animal food, on chestnuts, Indian corn, and potatoes (_Dupin_), while in England, malt, hops, sugar, brandy, tea, coffee, tobacco, soap, newspapers, etc. are described as "articles chiefly used by the laboring classes." (_Carey_.) The standard of decency of the working class also has great influence here. The use of blouses in Paris has nothing repulsive, nor that of wooden shoes in many of the provinces of France, nor the absence of shoes in lower Italy; while the English workman considers leather shoes indispensable, as he did only a short time ago a cloth coat. Compare _infra_, § 214.[162-4] [Footnote 162-1: Explained since _Liebig's_ time by the fact that a part of food is consumed to preserve animal heat: means of respiration in contradistinction to means of nutrition. Recent research has shown that in cold weather more urea and also more carbonic acid are given off; hence the means of supplying this deficit should be greater in cold weather than in warm. This more rapid transformation is wont, when nutrition is sufficient, to be accompanied by more energetic activity. (_Moleschott_, Physiologie der Nahrungsmittel, 1850, 47, 50, 83.)] [Footnote 162-2: This is opposed in part by the fact that a hot climate induces indolence, and that therefore he needs a greater incentive to overcome his disposition to idleness. Thus, in the cooler parts of Mexico, the rate of wages was 26 sous a day, in the warmer, 32 sous. (_Humboldt_, N. Espagne, III, 103.)] [Footnote 162-3: According to _Engel_, Jahrbuch für Sachsen, I, 419, on acres similarly situated and under similar conditions, the lowest yielded: _Watery contents _Watery contents included._ excluded._ Of wheat, 1,881 lbs. 1,680 lbs. " rye, 1,549 " 1,404 " " pease, 1,217 " 1,095 " " potatoes, 21,029 " 5,257 " The dry substance of these products yielded: _Azotized _Mineral Substance._ _Fecula._ Matter._