Just a bit of mansplaining on the impressive and beautiful drawing of Henry's wife. You won't often get to see drawings like this. When one is taking art classes, during early portions of drawing instruction, you are encouraged to work toward capturing your subject with quick, free applications of media... chalk, charcoal, pastel, etc.
The reason for this is that it teaches you to observe the subject and train your eye to move back and forth between your subject and the drawing in an almost machine-like process... but if followed, it trains you to not just look at the drawing because that's when you lose out and stop putting quick thought into what your hand should be doing to capture what you see (like in the drawing above).
It is sometimes called a "study" and is used as preparation for a more detailed drawing or painting.
Here is a quickly done drawing as an example how a drawing like that comes together. Some of it is sped-up, but that's to keep things moving for the viewer... the artist isn't working from a subject, however. Years of experience have allowed him to work as if he is.
https://www.facebook.com/reel/1029069048532120.