5i 



Cincinnati Society of Natural History 



The area of each is 45000 s(|uare feet, or together 90000 square 

 feet. This is loooo times 1296 S([uare inches. 



It is noteworthy that the phiy of the numbers used about these 

 works is the same that is so fiimiHar with us, in our measures of space 

 and time. 1296 square inches is one of our square yards, 4 of 

 which, or 5184, muUipUed by 1000 is the number of thirds in one 

 solar day of 24 hours, measured on the circle of 360 degrees, as 15 

 degrees to the hour. That is, a circle of 360 degrees forming 24 

 hours, reduced to minutes and seconds and tliirds give's 5184000'" as 

 parts It is the measure of time on such a circle that causes the 

 transfer of the measure of right-lined shapes onto circular ones, by 

 a fittingly chosen set of numbers, and the numbers 6, 12 and 36, 

 have always, and with all nations, been used as the numbers for 

 measures in common, for the two kinds of shapes, viz ; rectangles and 

 circles. 360X24 is 8640. The half of 864 is 432, and the play 

 upon this number is common among the nations, as 324, .243, etc. 

 324 is 36X9, as also io8X3> while 1080 divided by 3 is 360. The 

 illustration on Plate 24, page dd, given hereafter, gives this as an 

 area, viz: 90 feet by 360 feet, or 32400, with 240 by 360 which 

 gives 86400. The use is singularly that of the very ancient Baby- 

 lonians. 



GROUP II. A. 



This group is characterized by a great circle, whose diameter 

 is 1050 feet. The circle is connected with a rectangle. The illus- 



