The hand, as Bridgman pointed out somewhere, often shows emotion the face is trying to hide. The fist shows anger, the cupped hand can express acceptance or pleading. The spread hand expresses welcome or gratitude. In this tutorial, we're going to start looking at hand gestures, starting with one of the simplest: the hand reaching for something. This tutorial assumes that you have already looked at Drawing Hands, Part I: Basic Forms and Drawing Hands, Part II: Thumb and Palm.
In most gestures -- greeting, reaching, holding -- the thumb is away from the body of the hand:
The important thing here is the triangle formed by the muscles between thumb and hand. The outer side of this triangle runs roughly from the base knuckle of the index finger to the base knuckle of the thumb.
As will be seen in this and future tutorials, that triangle of muscle is an important feature of gestures of pointing, greeting, throwing, grasping, etc.
Let's look at a hand reaching down for something. We can start by drawing the end of the forearm, the wrist-bones block and the body of the hand.
The wrist tapers slightly towards the wrist, and the wrist bones (slightly shaded here) step down to the body of the hand (see Drawing Hands, Part I: Basic Forms). The body of the hand, seen from the back, spreads slightly towards the fingers. It ends at the knuckles. Doesn't look like much yet, but bear with me.
To start on the thumb, we draw a line starting at the wrist-bone block, where it joins with the body of the hand, and angling outward. That will be the outside of the thumb.
On that line, we put a couple of dots, for the thumb joints. The second thumb joint is in the arc of the knuckles (red arc). The first thumb joint is about half way back towards the wrist. I put a little bump here, because that knuckle usually sticks out some.
Now for the fingers. I'm putting some circles here for the knuckles, and drawing the fingers out past the body of the hand, spreading some.
Hand proportions vary a lot -- long fingers, stubby fingers, slender, fat. A rough rule for the length of the second finger is that the distance from the place where the forearm joins the wrist block, to the first knuckle (blue line), is the same as the distance from the knuckle to the end of the finger (red line).
Now I put some little circles where the finger joints go, and I draw little arcs between the fingers, for the end of the palm:
The arc of the palm end (red) is halfway between the arcs of the knuckles and the first joints of the fingers:
Now for the thumb. How do we give it form? First, it is a little thicker than the thickest finger:
Second, as I said before, there is a triangle of muscle between the base bone of the thumb, and the metacarpal of the index finger:
Third, when the fingers and thumb are spread like this, the tip of the thumb lies in the same arc as the arc of the fingers' first joints:
And that's it -- we have constructed the basic form of the hand reaching down, as seen from the back. Now we erase the scaffolding of our construction, all the dots and circles and so on, and put in some shading, and we have a half-way believable hand, reaching down.
Here's one drawn a bit less mechanically, but according to the same rules. This also shows the fingers spread out as widely as possible. Observe that the little finger can usually angle further out, away from the hand, than the index finger:
Obviously, we don't want to have to go through all this rigmarole, every time we want to draw a hand reaching down. And we don't have to. With practice, the anatomical rules outlined here become second nature. Really. Trust me on this one.