Hints to Travellers, Scientific and General, Vol. 2 / Tenth edition, revised and corrected

by Royal Geographical Society

Fig. 3.—Measurement of the length of the skull with another form of callipers.

8. Cranial measurements are made with callipers and a flexible steel or tape measure. These objects, as well as a graduated two-meter rod used for measuring stature or long bones, are supplied in a travelling case by Messrs. Hermann of Zürich, who have made them to Professor Martin’s designs. The whole outfit costs about £4, but the instruments can be obtained separately. Messrs. Hermann also make a modified form of the callipers, known as Flower’s Craniometer (cf. Fig. 2). Measurements are recorded in millimeters, in which the various callipers, etc., are graduated. The latter instruments may have the forms represented in Fig. 2 (Flower’s Craniometer) or Fig. 3, in which are shown the exact positions of the instruments in measuring the length of the skull.

The chief measurements may be now enumerated in order of importance:—

i. The extreme length of the brain-case, measured as shown in Figs. 2 and 3.

ii. The maximum breadth of the skull is measured on the brain-case.

iii. The circumference of the brain-case (as distinct from the face) is measured with the flexible tape passed round the brow-ridges and the back of the skull. The measurement is that of the greatest circumference of the brain-case obtainable in this way.

iv. Measurements illustrative of the degree of prominence of the upper jaw are two in number, and are made with the callipers. The two measurements start from the same point behind; this point is the middle of the front edge, or margin, of the hole for the spinal cord (foramen magnum), shown in Fig. 1, E. From this common point, the upper or basi-nasal measurement passes to the upper border of the nasal bones in the middle line of the face, and the lower or basi-alveolar measurement passes to the extreme front edge of the upper jaw in the middle line, just above and between the upper incisor teeth.

9. Measurements of the long bones of the limbs. These are best made by means of a graduated rod with fixed and movable limbs, resembling a large pair of callipers. Such a rod is supplied (as indicated above) by Messrs. Hermann. The bones to be measured are six in number for each side of the body, viz.:—those of the upper arm and thigh (humerus and femur); then two for the forearm (called radius and ulna, the former being the shorter); and two for the leg (called tibia and fibula, the former, or shin-bone, being the larger). The extreme or maximum length is measured in each case, excepting those of the femur and tibia.

i. The femur is measured obliquely, that is, from its ball-like head to a line touching both prominences at the lower end, as shown at B in Fig. 4. This represents the position of the bone in a person standing erect.