[DAWSON] SULAR AND LUNAR CYCLES IN BOOK OF DANIEL 39 



This indicates the degree of accuracy in the calendar now used by 

 most of the civilized nations. It is quite modern, however, as it was 

 only devised in 1582, and was not adopted in England until 1T5"3. This 

 may be emphasized, because years do not differ from each other in length 

 to the same extent as successive months do; and a correct mean value 

 for the lunar month is consequently much more difficult to obtain. 

 This should l)e taken into account in comparing the accuracy of the 

 lunar calendar and cycles under the next head. 



II. The lunar year and the day. — We here meet with the first 

 of the cycles based on the prophetic numbers. The number 1,260 

 mentioned in Daniel and in Eevelation, is designated as "3^2 times; "' 

 which is evidently half of the complete period of " seven times," as seven 

 represents completion in Scripture. Accordingly, the double of 1,260, 

 or 2,520 years, is the measure of this whole period. 



jSTow, the period of 2,520 lunar years, contains an exact number of 

 days. With the value adopted for the lunar year we have: — 



Lunar years 2520 x 354.3670644 = 893005.0023 days; 

 or 504 X do = 17860L0005 " 



Conversely, if we assume the cycle 504 lunar years :^ 178,601 days 

 to be exact at this epoch, we find the values following for the lunar 

 year and month, which we may term the " cycle-values " : — ' 



178(501 days -;- 504 = 354.3670635 for the lunar year; 



and 29.53058862 for the lunar month. 



The value of the lunar month thus arrived at, dift'ers from our 

 adopted value by only 0.000 000 08 of a day, or 0.007 of a second of 

 time. This is well within the limit of accuracy with which the synodic 

 month is yet known ; as it will be seen that these cycle-values lie between 

 Xeison's determination and Newcomb's, as above cited. This cycle may, 

 therefore, be designated exact at the epoch 1900 ; for if we were to 

 follow out the calculation at this epoch in the same way as for the 

 other cycles, the resulting error would be one day in 1,110,000 years. In 

 former centuries it will only be in error by the amount of the secular 

 acceleration of the moon. 



For comparison on the same basis as before, we may give here 

 the error at the other extreme; or at the beginning of the longer period 

 of twenty-five centuries, on which the cycle is based; or, say, in 600 B.C.. 

 The value of the lunar year at that epoch, with the largest value for 

 the secular acceleration (see figures under that heading) is 354-3671564 

 davs. 



