For so long a time has the oval been used as the basis for the construction of the human head and face that the use of the block or cube seems quite revolutionary.
Yet for many reasons the cube seems preferable. The oval is too indefinite, and offers no points for comparison, no basis for measurement. The eye does not fix on any point in a curved line.
On the ground plan of a square, however, any form may be built. The block moreover carries with it from any angle its perspective and its foreshortening, and it carries with itself the sense of mass.
Especially does it carry with itself the important element of the bilateral symmetry of the head -a symmetry that is present indeed in all living things. A vertical line in the centre divides the head or the trunk into parts equal, opposite, and comple-mental. The right eye is the counterpart of the left; the two halves of the nose are symmetrical; the limbs, except for changes of position, are exact though reversed duplicates of each other.
How to construct such a block?
Camper, Professor Bell, and others have studied innumerable human skulls trying to discover some constant measurement by which to classify them as ancient or modern or according to race. They finally fixed upon two lines with the angle between them. The first passes from the base of the nose to the roof of the ear canal; the second passes from the upper incisor teeth to the prominent part of the forehead.
The angle between these lines is practically constant for a given race or a given age of evolution. Individual variations occur, but they are less than the standard.
This angle is less in the older and less evolved races, and the vertical line approaches nearer the perpendicular in the newer races, especially the Caucasian. In the classical Greek head it even passes the perpendicular, although no actual Greek skulls in which this is the case have ever been discovered.
This angle, in the Caucasian races, is about eighty degrees. It is not easy to construct a block on such an angle, and it is very desirable to have a right angle. By dropping the horizontal line at its rear end from the roof of the ear canal to the tip of the ear lobe, and by drawing the vertical line from the base of the nose where it joins the upper lip to the bridge of the nose, where it joins the glabella, we obtain such a right angle.
If on these straight lines a cage be built, bounding the head and face, it will be found that the front and back are oblong and the sides are square.
The top of the cage should be level with the top of the head, the bottom with the bottom of the chin; the border of the cheek should fit the sides. The length of the oblong front will equal one and three-quarters times its width. The cheek bones set back from the front of the cage about one-third of the distance to the ear.
Blocked Construction Of The Head.
The Head. Eminences. Ridges and Depressions of the Skull.
The Head. The Angles of Construction.
Text Page 114.
The Head. Muscles of Mastication.
3 Buccinator (cheek muscle).
4 and 5. Lesser and greater zygomaticus (muscles of expression).
The masses of the head are the cranium, the skeleton of the face, and the jaw.
Into the rounded mass of the cranium sets the. narrower mass of the forehead hounded by the temples at the sides and by the brows below.
From the lower outer corners of the forehead the wedge of the cheek bones begins; moves outward and downward until it just passes the curve of the cranium, then down and in, in a long sweep, to the corner of the chin.
Outside of and behind this lower line is another wedge, that of the corner of the jaw, with the line itself for base, and a very low apex.
The two cheek bones form together the central mass of the face, in the middle of which rises the nose.