Therefore

20 If two solids be alike, they have their sides proportionalls, and two meane proportionalls 21 d vij, 19. 21. p viij.

It is a consectary out of the [5 e xxij]. But the meane proportionalls are made of the sides of the like solids, to wit, of the second, third, and fourth: Item of the third, fourth, and fifth, as here thou seest.

2, 3, 5, 4, 6, 10.
30,60,120,240.

Of Geometry the twentie fourth Book. Of a Cube.

1 A Rightangled parallelepipedum is either a Cube, or an Oblong.

2 A Cube is a right angled parallelepipedum of equall flattes, 25. d. xj.

As here thou seest in these two figures.