Pen & Ink Drawing Tutorials | How to shade the arm with crosshatching

How to draw tips on shading or rendering with hatching and crosshatching as a part of learning how to draw with pen and ink. I used a Lamy Safari fountain pen. How to use line variation, as in line weight is my main focus here. How to vary line weight or thickness to convey light and shadow and describe volume. I used a part of a drawing by Hendrick Goltzius as a reference for pointing out some useful techniques you should practice or at least be aware of when drawing with pen and ink using a fountain p