The yellow/blue cube in f102v2

[stellar]

Perhaps this can be viewed as a question of which of these things is not like the others. Isn't it generally perceived that this is a "recipe" section and the items illustrated are ingredients, not *products*. Soap would be a product, not an ingredient.

Meanwhile I seem to recall Lapis was an occasional ingredient in the manufacture of certain medical treatments, IIRC.

Recipe section is as good a guess as any other, if you are compiling a list of the various possible functions, but...

there's no proof or even strong evidence yet that this is a recipe section. Recipes (whether culinary or medical) were not typically illustrated in the middle ages. They were almost always textual.

It's certainly possible that they are ingredients, maybe even the most likely explanation, but I can think of a couple of other possibilities so... until more is known, I personally prefer to call it the small plants section (as in small-drawn plants) and not assume its function.

In Monas Hieroglyficae,

John Dee deals with cubes and Pi.

The hypothesis set forth is that John Dee intended for the culmination to occur in Theorem XX by designating and thereby demonstrating a solution of the duplication of the cube. To affect this he embraces alternative methods employing the use of conic sections, acknowledging the non-existence of a classical solution, something that was only shown centuries later, and contrary to the contemporary attitude toward the quest for solutions. By considering these methods he is not accepting defeat; rather by so doing he utilizes geometrical concepts not in use until much later. This strongly suggests his awareness of geometry beyond the earthly three dimensions.
According to historian of science J. L. Heilbron, in the introduction to the translation of the Propaedeumata AphoristicaDee really did have interest in the duplication problem, the construction of a cube with twice the volume of a given cube, for "there are two noteworthy points about Dee’s problems. First, they are inspired by the ancient, unresolved problems of squaring the circle and, above all the doubling of the cube."You are not allowed to view links. Register or Login to view. Second, the significance of the problem stems metaphysically from the story of a plague in Athens; after the oracle at Delos was consulted, in order to appease the sun god Apollo they were required to double the size of the cubical alter. Thus it is often referred to as the Delian problem.
For a thorough understanding of what John Dee was implying by the use of his Hieroglyphic Monad as an explanation of the duplication problem, and how it foreshadows the impossibility of construction of necessary points, including the ultimate transcendental nature of π, an investigation of the later development of algebra unto the nineteenth century becomes necessary.
http://www.jwmt.org/v2n19/Delian.html