The ancient methods of dividing day and night in China and Japan become more hazy as we go backwards and the complications grow. The three circles in Fig. 1 (Chapter I) are all taken from Japanese clocks, but the interpretation has been obtained from Chinese and Japanese scholars. The Japanese obtained a great deal from the Chinese, in fact nearly everything relating to the ancient methods of time keeping and the compiling of calendars. I have not been able to find any Chinese clocks constructed of wheels and pinions, but have a number of Japanese. These have a distinct resemblance to the earlier Dutch movements, and while made in Japan, they are practically Dutch, so far as the "works" are concerned, but it is easy to see from the illustrations that they are very Japanese in style and ornamentation. The Dutch were the leaders in opening Japan to the European nations and introduced modern mathematics and clocks from about 1590 A. D. The ancient mathematics of Japan came largely from China through Corea. In Fig. 11 are given the Japanese figures beside ours, for the reader's use as a key. The complete day in Japan was divided into twice six hours; that is, six for daylight and six for night, and the clocks are set, as the days vary in length, so that six o'clock is sunrise and sunset. The hour numerals on Fig. 12 are on little plates which are movable, and are shown set for a long day and a short night. [Illustration: Fig. 11] [Illustration: Fig. 12 Fig. 13. Japanese Dials Set for Long and Short Days]