Note 261 — IS THE GREAT PYRAMID OF GIZEH A METROLOGICAL MONUMENT?

Thus, after deducing the length of the cubit of Memphis from the length of the King's Chamber, Sir Isaac Newton observes:—"From hence I would infer that the Sacred Cubit of Moses was equal to 25 unciæ of the Roman foot and 6/10 of an uncia." (See his Dissertation on the Sacred Cubit, as republished in Professor Smyth's Life and Work at the Great Pyramid, vol. ii. p. 362.) Again, at p. 363, Sir Isaac speaks of "the cubit which we have concluded to have been in the time of Moses 25-60/100 inches" of the Roman foot; and at p. 365, in closing his Dissertation, he remarks—"The Roman cubit therefore consists of 18 unciæ, and the Sacred Cubit of 25-3/5 unciæ, of the Roman foot." In other words, according to Sir Isaac Newton, the Sacred Cubit of 25·60 inches of the Roman foot is equal to 24·75 British inches; for, as he calculated, the Roman foot "was equal to 967/1000 the English foot." (See p. 342.) This is the measurement of the Roman foot laid down by Sir Isaac Newton in his Dissertation, and the only standard of it mentioned in Professor Smyth's Life and Work at the Great Pyramid; yet in that work Professor Smyth calculates Sir Isaac's Sacred Cubit to be 24·82 instead of 24·75 British inches. In doing so, he has calculated the English foot as equal to ·970 of the Roman foot; but was he entitled to do so when using Sir Isaac's own data, and when employing Sir Isaac's own calculated conclusion as to the length of the Sacred Cubit? In the published Proceedings of the Royal Society, in consequence of following the calculation by Professor Smyth of Sir Isaac Newton's conclusion from Sir Isaac's own data as to the length of the Sacred Cubit, it was erroneously spoken of as 24·82, instead of 24·75 British inches.