The 墨经/MoJing is the portion of the MoZi text dealing with Mohist logic, nominalism and the reification of names, mathematics, geometry, the mechanics of force, optics science and other natural sciences.
My Chinese copy of the 墨经/MoJing has many fascinating diagrams derived from the Mohist discussion on geometry and the sciences. Would like to scan and place some of them here.
In the meantime, here is the Stanford Philosophy server on the Mohist Canon (but without their mathematics and science portions):
And here’s what English wiki says (woefully thin) of the 墨经/MoJing: