The diagram below is from a previous post, the new added information is at the top and the bottom
As previously said an equilateral triangle can be formed based on the distance between G1 and G3, Petrie gives this measure as some 36858" , i maintain the intention was 6" longer at 36864" or 3072 ft
So if we take the three sides of the triangle as diameters of circles then this is what we can find.
3072 x 3 x Pi / 3.6526 = 7926.6 read as miles
Now its 0.2 miles bigger than todays 7926.4 miles , so is the bigger figure alluding to some sort of Earth change ?.