According to Cassini, a degree was 600 stadia, a minute 10 stadia; and a modern Italian mile, in the year 1723, was equal to one and a quarter ancient Roman miles; and one and a quarter ancient Roman miles were equal to ten stadia or one minute. (Cassini, Traite de la grandeur et de la Figure de la Terre. Amsterdam, 1723.)

Fig. 5

R.B.
Cubits.
R.B.
Cubits.
FB = 640EB = 504
BA = 672BA = 672
AF = 928AE = 840
DC = 1080NO = 768
CA = 1440OF = 1024
AD = 1800FN = 1280
DG = 576AY = 288
GE = 768ZY = 384
ED = 960ZA = 480
R.B. Cub.
At level of Cephren's Base which is
the plane or level of the plan
.—
}{Cheops' Base
Cephren's Base
Mycerīnus' Base
420
420
218

Dufeu also made a stadium the six hundredth part of a degree. He made the degree 110827·68 metres, which multiplied by 3·280841 gives 363607·996+ British feet; and 363607·996+ divided by 600 equals 606·013327 feet to his stadium.

I make the stadium 606·62376 British feet.

There being 360 cubits to a stadium, Dufeu's stadium divided by 360, gives 1·6833 British feet, which is the exact measure given for a Royal Babylonian Cubit, if reduced to metres, viz.: 0·5131 of a metre, and therefore probably the origin of the measure called the Royal Babylonian cubit. According to this measure, the Gïzeh plan would be about 1/1011 smaller than if measured by R.B. cubits.

§ 3. THE EXACT MEASURE OF THE BASES OF THE PYRAMIDS.