Near the southern end of the bridge the boys observed something like a great sign-board with a railing around it, and a roof above to keep the rain from injuring the placards which were painted beneath. The latter were in Japanese, and, of course, neither Frank nor Fred could make out their meaning. So they asked the Doctor what the structure was for and why it was in such a conspicuous place. "That," answered the Doctor, "is the great kosatsu." Frank said he was glad to know it, and he would be more glad when he knew what the kosatsu was. [Illustration: THE GREAT KOSATSU, NEAR THE NIHON BASHI.] "The kosatsu," continued Doctor Bronson, "is the sign-board where the official notices of the government are posted. You find these boards in all the cities, towns, and villages of Japan; there may be several in a city, but there is always one which has a higher character than the rest, and is known as the _great_ kosatsu. The one you are now looking at is the most celebrated in the empire, as it stands near the Nihon Bashi, whence all roads are measured, as I have already explained to you." "Please, Doctor," said Frank, "what is the nature of the notices they put on the sign-board?" "Any public notice or law, any new order of the government, a regulation of the police, appointments of officials; in fact, anything that would be published as an official announcement in other countries. There was formerly an edict against Christians which was published all over the empire, and was on all the kosatsus. The edict appeared on the kosatsu of the Nihon Bashi down to the overthrow of the Shogoon's government, in 1868, when it was removed." "And what was the edict?"