抄録
It has been ascertained by experiments that the spraying of the leaves and stems of wheat seedlings with the solution of hot-spring mud and water had a marked effect on the development of the roots. The solution was made by mixing 10 g. of hot-spring mud with 100c.c. of water and then putting the mixture into a glass-bottle whose capacity is 25Oc.c., with its mouth being tightly corked and the mixture being let alone for a month at the temperature of 25°C., and for this experiment only the clear liquid part which gathered on the top of the mixture was used. This clear liquid part of the mixture proved to have the same effect on the etiolated leaves of wheat. The increase in the weight of roots is chiefly due to the branching off of more roots. The writer says that this phenomenon is due to the radioactivity of the said hot-spring mud.
