336 SYSTEMS OF PERMANENT AGRICULTURE 



more in' extent, that are not now populated, the reclamation of 

 which has been called the " Problem of China." 



The information available is not sufficient to determine to what 

 extent the waste lands of India and China represent abandoned 

 farms that were once cultivated, but it is fully known that to some 

 extent this is the case. On the other hand, the Chinese have main- 

 tained well the fertility of much of the lands they are now culti- 

 vating. The explanation is found in the following quotations, taken 

 largely from Sir Humphry Davy's " Agricultural Chemistry " (1827) 

 and from Davis, Fortune, and other writers, through extracts 

 published in the works of Baron Justus von Liebig (1840 to 1859) : 



"The Chinese, who have more practical knowledge of the use and application 

 of manures than any other people existing, mix their night soil with one third 

 of its weight of a fat marl, make it into cakes, and dry it by exposure to the sun. 

 These cakes, we are informed by the French missionaries, have no disagreeable 

 smell, and form a common article of commerce of the empire." DAVY. 



"Davis, in his ' History of China,' states that every substance convertible into 

 manure is diligently husbanded. 'The cakes that remain after the expression 

 of their vegetable oils, horns, and hoofs reduced to powder, together with soot 

 and ashes, and the contents of common sewers are much used. The 

 plaster of old kitchens, which in China have no chimneys, but an opening 

 at the top, is much valued : so that they will sometimes put new plaster on 

 a kitchen for the sake of the old. All sorts of hair are used as manure, and 

 barber's shavings are carefully appropriated to that purpose. The annual 

 produce must be considerable, in a country where some hundred millions of 

 heads are kept constantly shaved. Dung of all animals, but more especially 

 night soil, is esteemed above all others. Being sometimes formed into cakes, 

 it is dried in the sun, and in this state becomes an object of sale to farmers, 

 who dilute it previous to use. They construct large cisterns or pits lined 

 with lime plaster, as well as earthen tubs sunk in the ground, with straw 

 over them to prevent evaporation, in which all kinds of vegetable and animal 

 refuse are collected. These, being diluted with a sufficient quantity of liquid, 

 are left to undergo the putrefactive fermentation, and then applied to the land." 



"Human urine is, if possible, more husbanded by the Chinese than night soil 

 for manure ; every farm, or patch of land for cultivation, has a tank where all 

 substances convertible into manure are carefully deposited, the whole made 

 liquid by adding urine in the proportion required, and invariably Applied to 

 the soil in that state. The business of collecting urine and night soil employs 

 an immense number of persons, who deposit tubs in every house in the cities 

 for the reception of the urine of the inmates, which vessels are removed daily 

 with as much care as our farmers remove their honey from the hives. The 

 night soil is collected in the same way, as well as on the roads and by-places, 



