26.
of the Nautical Almanac .
From the moon's age, exhibited in the Nautical Almanac we find the Chinese date by help of the simple rule : if the decimal fraction of the age is smaller than 9, add one to the number of whole days of the age ; if the decimal fraction equals 9, add two to the number of the whole days of the age ; the sum will be the Chinese date (Peking time). For, when the age, according to the Nautical Almanac, e. g. today at Greenwich noon is 0,d9, the Newmoon or the 1th Chinese date was a day before at 0,d1 P.M. Greenwich time or 0,d1 +0,d32 = 0,d42 Peking mean time in the afternoon; therefore to day, for which the Nautical Almanac gives the age 0,9, is the second of the Chinese month i.e. we have to add to the integer of 0,9, which is in this case zero, 2, in order to get the Chinese date ; the same rule holds good for all following days, for which the age is resp. 1,9 2,9 3,9…. When the Nautical Almanac's age is 0,d0 or 0,d1 or 0,d2 ... or 0,d8, the W d M., Newmoon takes place to day at respectively 0,32 P.M., 0.,2.2. P. d . A.M., 0,02 0,12 P. M., 0,02 P.M., 0,42 A. M. , 0, 32. A. M., 9, 22. A. M., 6,42 A. M. Peking time, therefore today is the ith day of the Chinese month and we add only 1 to the integer, belonging to the moon's age.
The calculation ofthe time, when the sun enters the 24 tsie-khi can be made either by using the astronomical fundamental tables, or, which is shorter, the Nautical Almanac. For instance : According to the Nautica lAlmanac for 1880 page 4 : January 5 at noon of Greenwich the sun's longitude 284 ° 35, 3 " J! 285 36,5 " " " !! 6 therefore the sun's longitude increases 1'in 1' in 24hours and 24,7 in 242.24,1 hours or 944m, that is, January 5 at 9441m Greenwich time the sun had the longitude 285 ° or entered the tsie -khi Sias Han. The Chinese Calendar date of Siao Han will be January use Peking time, which is 7448before 6 shaymA.M.,because they the Greenwich time, and in the Nautical olmanac commences the day with noon, but in the Calendar with midnight.
Since the entrance of the sun in the 12 signs of the zodiac always occurs about the 21th of the European months and the European date of the Newmoon recedes every year about 11 days or every month nearly one day, the date of the Newmoon must pass the 21th of the European month every two or three years. About this passage we will meet a Lunation , which fullfills the conditions of the Chinese intercalary month. [see Table (25) and the following text]. This , for example , was the case with the 4th Lunation of the year 1879 A.D., because there
