The boys had observed that the farther they penetrated from Yokohama and Tokio, the less did they find the people affected in their dress and manners by the presence of the foreigners. Particularly was this the case with the women. They had seen in the open ports a good many women with blackened teeth; and the farther they went inland, the greater did they find the proportion of the fair sex who had thus disfigured themselves. So at the first opportunity they asked the Doctor about the custom. "I know," said Frank, "that it is the married women that blacken their teeth; but how does it happen that there are so many more married ones here than on the shores of Yeddo Bay?" "You are wrong there," answered the Doctor; "there is probably as large a proportion of married women in the one region as in the other. The difference is that the custom is rapidly falling off." "Is there any law about it?" Fred inquired. "Not in the least," Doctor Bronson explained. "It is an old custom for married women to blacken their teeth, and formerly it was most rigidly observed; but of late years, since the foreigners came to Japan, it has not been adhered to. The Japanese see that a married woman can get along without having her teeth discolored, and as they are inclined to fall into the customs of Europe, the most progressive of them not only permit, but require, their wives to keep their teeth white." "That is one point," said Frank, "in which I think the Japanese have gained by adopting the European custom. I don't think it improves their appearance to put on European clothes instead of their own; but when it comes to this habit of blackening the teeth, it is absolutely hideous." From this assertion there was no dissent. Then the question naturally arose, "How is the operation performed?" Doctor Bronson explained that it was done by means of a black paint or varnish, peculiar to Japan. The paint was rubbed on the teeth with a rag or stiff brush, and made the gums very sore at first. It remained quite bright and distinct for the first few days, but in the course of a week it faded, and by the end of ten or twelve days a renewal was necessary. If left to itself, the coloring would disappear altogether within a month from the time of its application.