Biorbital diameter: between the two external borders of the orbits.
Gonio-mental distance: from the goniac point to the point of the chin.
Auriculo-frontal radius: from the tragus or from the auricular point to the ophryon.
Auriculo-subnasal radius.
Auriculo-mental radius.
(The last four measurements, if compared right and left, give an index of facial symmetry; the radii when compared together serve as an indirect measure of prognathism.)
Width of nose between the external borders of the nostrils (the branches of Mathieu's compass are placed tangent to the nostrils).
(The index of the nose is obtained from the length and breadth, by applying the well-known formula of indices; the nose thereupon receives various names—leptorrhine, mesorrhine, platyrrhine).
Width of orbit: from the inner extremity of the ocular rima (eye-slit) to the external border of the orbit.