20 BROWN : 



It cannot fail to strike any one who looks at this block that 

 here is the foreshadowing- of a calendar. Lines of seven, as 

 in the days of the week, horizontal!}' ; columns of twelve, as 

 in the months, vertically. 



It will be seen at once that, taking any letter and counting 

 back or fonvard from it seven, we shall come round to the 

 same letter. 



It will be seen that taking any letter that falls under a 

 number which is the ordinal of the last day of the month it is, 

 with one exception, the letter next following alphabetically 

 which will stand under the number i above and represent the 

 first of the next following month. 



The exception is D when it stands for the 29th of Febru- 

 ary-. In this case D becomes the letter for the first of March 

 also, because the Sunday Letter changes at this point for the 

 last of the year. The letter backs one and shoves, as it were, 

 D, as first of March, over into the place occupied by the 29th 

 of Februan.-, so that there is a lap at the first of March which 

 takes up the excess. The block is permanent in its present 

 form and will sen-e for any year whatever of the Christian Era. 



In order to a full understanding of the matter some discus- 

 sion of the years previous to 1582 is desirable. 



The Julian Calendar Reformation, 46 B. C, fixed 365 

 days and a quarter as the length of the civil year, and one day 

 in ever>' four years was interpolated to use up the excess. 



But a quarter of a day corrects too much. The civil year 

 is in fact 



365 days, 5 hours, 48 minutes, 46. 48 seconds, or 

 365.2422 days long, and not 

 365 days, 6 hours, or 

 365.25 days long. 

 When the sun enters the first point of Aries, four years after 

 the last leap year, the earth has made, not 365.25 X 4 turns = 

 1461, but 365.2422 X 4= 1460.9688 turns. The fourth yeaiiy 

 revolution is complete before the last diurnal turn is finished, 



