“As with Dee’s Pythagorean speculations, here, too, we find instances of later writers either directly referring to Dee or at least making use of similar techniques. Petrus Bungus’s Numerorum Mysteria (1618), for instance, refers the reader to Dee’s Monas Hieroglyphica in a discussion of the letter X and the significance of the point at the intersection of the four radiating lines, with unity denoting God and a good intellect, and duality a demon and bad intellect.
Dorn, in another of his scholia to the Tractatus Aureus, this time commenting on Hermes’ ruminations on the symbolism of a hen’s egg, takes Dee’s Roman numeral speculations in Theorem 16 a stage further.
He argues that the two letter Vs which mirror one another represent, as it were, the “As above, so below” maxim of the Emerald Tablet, with the upper V being incorporeal, and the lower corporeal. When these two are brought together, they form the letter X, i.e. the denarius or number of perfection, represented otherwise by the letters IO, as if one were saying “one circle,” or one revolution of a circle, this denary number being the Mercury of the Philosophers.
In addition, the Roman letter M equals the number 1,000, which is the ultimate perfection of all other numbers, and for Dorn denotes sulfur, which (containing fire, the fifth essence, and spirit) makes all things bear fruit.
If you join all these letters together, you get the word OVUM; the letter O signifies earth, for philosophical earth should be round and circular like the motion of the heavens; the letters VU represent water and air, and the final letter M represents fire (possibly because it resembles the astrological glyph for Aries ) — all combining to make the word “EGG.”
–Peter J. Forshaw, “The Early Alchemical Reception of John Dee’s Monas Hieroglyphica,” AMBIX, November, 2005, pg. 253.