Rubens in his “Descent from the Cross” has avoided these disagreeable angles, but in many of his more careless compositions, where there is violent action, they are painfully conspicuous, in spite of his liberal use of flying draperies. Hence his cavalry skirmishes, though full of violence and contortion, are quite wanting in spontaneous “go.”
Right angles in a group of figures convey the idea of immovability. Hence, although generally undesirable, it is well sometimes to introduce them.
Thus a kneeling warrior firmly planted to resist onslaught might with propriety have both knees right angles.
In this case we wish to give the idea of fixture, and therefore rectangular forms are not only allowable but very useful. Again, in the case of a wounded man endeavoring to raise himself, the angle formed by his right arm might with propriety be a right angle, because we want to show that the man is wounded and cannot raise himself without difficulty.
If he were uninjured and in full possession of his strength, we ought to represent his springing up in some other way.
In the very frequent case of two arms crossing each other, they should not cross at right angles.
There is no reason here for expressing immovability at the point where the arms cross, and therefore the formality of right angles should be avoided.