rails, securing the greatest economy of fuel, providing the guests with places where they may sit upon the moderately warmed fireplace, and spread their beds when they retire. The economy of the chimney beds does not end with the warmth conserved. The earth and straw brick, through the processes of fermentation and through shrinkage, become open and porous after three or four years of service, so that the draft is defective, giving annoyance from smoke, which requires their renewal. But the heat, the fermentation and the absorption of products of combustion have together transformed the comparatively infertile subsoil into what they regard as a valuable fertilizer and these discarded brick are used in the preparation of compost fertilizers for the fields. On account of this value of the discarded brick the large amount of labor involved in removing and rebuilding the kangs is not regarded altogether as labor lost. Our own observations have shown that heating soils to dryness at a temperature of 110 deg C. greatly increases the freedom with which plant food may be recovered from them by the solvent power of water, and the same heating doubtless improves the physical and biological conditions of the soil as well. Nitrogen combined as ammonia, and phosphorus, potash and lime are all carried with the smoke or soot, mechanically in the draft and arrested upon the inner walls of the kangs or filter into the porous brick with the smoke, and thus add plant food directly to the soil. Soot from wood has been found to contain, as an average, 1.36 per cent of nitrogen; .51 per cent of phosphorus and 5.34 per cent of potassium. We practice burning straw and corn stalks in enormous quantities, to get them easily out of the way, thus scattering on the winds valuable plant food, thoughtlessly and lazily wasting where these people laboriously and religiously save. These are gains in addition to those which result from the formation of nitrates, soluble potash and other plant foods through fermentation. We saw many instances where these discarded brick were being used, both in Shantung and Chihli provinces, and it was common in walking through the streets of country villages to see piles of them, evidently recently removed.