Another equally, or even more, laborious practice followed by the Chinese farmers in this province is the periodic exchange of soil between mulberry orchards and the rice fields, their experience being that soil long used in the mulberry orchards improves the rice, while soil from the rice fields is very helpful when applied to the mulberry orchards. We saw many instances, when traveling by boat-train between Shanghai, Kashing and Hangchow, of soil being carried from rice fields and either stacked on the banks or dropped into the canal. Such soil was oftenest taken from narrow trenches leading through the fields, laying them off in beds. It is our judgment that the soil thrown into the canals undergoes important changes, perhaps through the absorption of soluble plant food substances such as lime, phosphoric acid and potash withdrawn from the water, or through some growth or fermentation, which, in the judgment of the farmer, makes the large labor involved in this procedure worth while. The stacking of soil along the banks was probably in preparation for its removal by boat to some of the mulberry orchards. It is clearly recognized by the farmers that mud collected from those sections of the canal leading through country villages, such as that seen in Fig. 10, is both inherently more fertile and in better physical condition than that collected in the open country. They attribute this difference to the effect of the village washing in the canal, where soap is extensively used. The storm waters of the city doubtless carry some fertilizing material also, although sewage, as such, never finds its way into the canals. The washing would be very likely to have a decided flocculating effect and so render this material more friable when applied to the field. One very important advantage which comes to the fields when heavily dressed with such mud is that resulting from the addition of lime which has become incorporated with the silts through their flocculation and precipitation, and that which is added in the form of snail shells abounding in the canals. The amount of these may be realized from the large numbers contained in the mud recently thrown out, as seen in the upper section of Fig. 95, where the pebbly appearance of the surface is caused by snail shells. In the lower section of the same illustration the white spots are snail shells exposed in the soil of a recently spaded field. The shells are by no means as numerous generally as here seen but yet sufficient to maintain the supply of lime.