Quote 'And if the Earth were a perfectly round sphere, that angle would be the equivalent of the actual Median degree value of the Earth. But for some as yet unknown reason to me, the ancients decided to place that Old Meter Median degree value at precisely 1224 arc. sec. lower than the 45* point on the sphere of the Earth. But that location is still a lot better than what the current Modern Meter difference from 45* is,'
Yeah there is a mystery and the ancients invented it.
The number 24750 miles has been around for a long time as an earth measure google it up. The thing that is interesting is that your number 7875 works with 22/7 = 24,750 and it connects with the pyramid 756.25 imperial feet exactly 440 Royal cubits 20.625 inches.
At the equator 1 degree of latitude 68.707 miles and the base of the pyramid is 7.5 seconds or 68.707 / 480 = 9069.324 inches. The sphere the ancients were working on re the casing base of the pyramid are those 68.75 x 360 = 24750.
The socket sides however and will use Petries 9125.9 inches 760.49 feet.
760.49 x 4 = 3041.96 .... 30 seconds of one degree
6083.93 one minute of a degree
x 60 = 365036 feet one degree (look at the number in feet 365)
69.1356 miles x 360 = 24,888.818
Two things here
1. We know 24883.2 = 69.12 x 360 and the diameter = 7920 using 3.1418181818
2. The old Egyptian value for pi 3.160493827 can be used with your number 7875 = 24,888.88888
Working back using 24,888.88888 / 360 = 69.13580247 / 60 = 1.52263374 miles = 5996083.9506 feet / 8 = 760.4938 feet the socket side of pyramid 9125.925 inches (Petrie 9125.9 inches).
There is a lot more to this and perhaps if you could work your rads again we may find it.