Although this may appear incomprehensible and contrary to the opinion of many, I shall, if God wills, make it clearer than the sun, at least to those who are not ignorant of mathematics.
"The order of the spheres is as follows: The first and lightest of all the spheres is that of the fixed stars, which includes itself and all others, and hence is motionless as the place in the universe to which the motion and position of all other stars is referred.
"Then follows the outermost planet, Saturn, which completes its revolution around the sun in thirty years; next comes Jupiter with a twelve years' revolution; then Mars, which completes its course in two years.

The fourth one in order is the yearly revolution which includes the earth with the moon's orbit as an epicycle.

In the fifth place is Venus with a revolution of nine months.

The sixth place is taken by Mercury, which completes its course in eighty days.

In the middle of all stands the sun, and who could wish to place the lamp of this most beautiful temple in another or better place.