I agree with you that it is ratios which are important, so it actually makes no difference to my model if the base of Khafre's pyramid was 410 cubits or 411 cubits because the height is 2/3 multiplied by the side length of the base.

I will be explaining my model for a length of 411 cubits because this is the only way that I can communicate with those who insist that we know that the cubit was 20.62 inches.

I promoted the side length of Khafre's pyramid as 411 cubits in my monograph on the Grand Gallery of the Great Pyramid, as published in 2006.
This may well be so, but I can't rule out an intended length of 410 cubits.

My personal view is that I can't prove the length of the cubit was 20.62 inches to my satisfaction, but its not a matter of importance if something far more important is apparent from the ratios.

Petrie was quite happy to include various propositions which if tenable mean that a question mark must be applied to the conventional view.

You digressed to the Great Pyramid as an objection to the proposed design of Khafre's Pyramid rather than considering that your long held cherished view of the relationship between the pyramids might be incorrect, and then identify me as in the same category as your friend which is reasonable if you also include all others who disagree with your 'inch theory'.

Can I ask who agrees with your theory on the inch / cubit relationship?

I followed your digression in order to make the point that I did not need to invent different lengths for the length of the cubit to support different theories on different pyramids.

I think I am the only person to have published a drawing showing the relationship between the chamber's walls and the size and shape of the Great Pyramid on a scale of one digit to one royal cubit which I did on the basis of a perimeter of 1760 digits, with 560 digits for the top of the wall, 560 digits for the bottom of the wall and 5 courses of 64 digits so a wall height of 320 digits.

This model, if so, would mean that the ratio 22/7 was the basis of the design, but I agree with Petrie and Smyth that a more precise Pi ratio was known.

My new model shows that at 22/7 cubits below the ceiling the ratio is accurate to better than 1 part in 30,000 from a straightforward conversion to lengths in digits which are conspicuously close to whole numbers of digits for a cubit of 20.65 inches. The proposed model indicates the height of the pyramid should be precisely 559/2 cubits with the side length of the base taken as 410 cubits, and the latter requires a cubit of 20.65 inches.

It is a pity that Petrie did not report his measurements but chose to modify his measurements by introducing a theory that the length of the chamber had increased by the width of cracks, so he subtracted the cracks from his measurements. This was a very poor presentation of results, but he was an young amateur surveyor not an experienced professional scientist.

Petrie did not publish what he had actually measured but what he thought had been the original size, having failed to appreciated that cracks in the long walls would not have changed the length of the chamber.

All the theories on the precise length of the cubit as 20.62 inches stem from Petrie's flawed analysis of the King's Chamber.

Petrie promoted a length of 20.64 inches in 1877, but others thought it was longer, typically around 20.66 inches, and some thought over 20.7 inches.


Mark