"And why couldn't _you_ say it before Clara put it into your head by saying 'Overshoes?" asked Miss Harson. "Clara has the right idea, only she did not express it in the clearest way. The sap of the caoutchouc, or India-rubber, tree is the most valuable yet discovered, and, as it is of a milky nature, it can very properly be brought into the present class of trees."