Not the least curious among Korean institutions is the system of communication maintained at the present time. At the yok, or post stations, represented on the map by diminutive circles, are kept numbers of the small active native horses, well fed and in good condition, attended by staffs of native couriers who are ready to receive orders from the station-master and spring into saddle upon a moment's notice. The service is well patronized and the couriers frequently employed, partly at the instance of the government, who desire to promote the efficiency of the system, and partly owing to the general accumulation of private needs of various kinds. A letter or parcel is thus rapidly transmitted from relay to relay, moving onward by day and night--except in certain mountainous districts of the north, where the fear of the tiger prevents night travel. Supplies of fruit and game for the royal table are forwarded in this manner to the capital from the most distant parts of the kingdom. The pong-wa, or signal-fire stations, are indicated upon the map by small squares placed at the summit of the mountains. They are especially numerous in the coast districts, where their sites are chosen with great care, in such manner that the fires that are lighted at each station at night-fall may be observed at some advanced point of the interior, whence a single fire may be again flashed on, to form a member of a more extended group. And so the lights proceed, re-collected and re-forwarded until the final combinations are gathered into a final group at the capital, to show that all is well throughout the kingdom. The faint network of lines extending over the whole country, as shown in the map of the southeastern province, represents the chief public highways, upon the determination of whose length and relative bearing the development of the map is based. In general, roads in Korea are well maintained, and during the greater part of the year are in fair condition. It would be found impossible to take a wheeled vehicle of any kind over them, however; for such use they are not intended, travel in Korea being performed afoot, or with the aid of horse or sedan. During the summer rains the streams rise rapidly; the waters pour down from the mountains, each rivulet becomes a torrent and the bridges are swept away. When the floods subside the local authorities compel the peasants to turn out in force and make the necessary repairs; delays of travel are thus reduced to a minimum.