REPORT ON THE HUMAN CRANIA. 
9 
In this way uniform results can undoubtedly be arrived at, but as is now admitted 
the cubage so obtained gives a higher numerical value to the contents than is the actual 
capacity of the cranium as tested by the employment of water for the purposes of cubage. 
This is not to be wondered at when it is remembered that the shot is rammed into the 
cranial cavity to its utmost capacity, whilst no corresponding pressure is applied to the 
shot after pouring it into the cubic measure, so that necessarily it occupies a greater 
space in the measure than in the skull. Dr. E. Schmidt, whilst recognising that Broca's 
method is not only the most practicable, but also the most precise of all the methods 
up to that time employed, has yet found it necessary to draw up tables by means of 
which the measurements taken according to Broca may be reduced to the actual capacity. 
Thus when shot is employed, whilst Broca's method would give 1000 cubic centimetres, 
the actual capacity is 931, making a difference of 69, and the difference gradually rises 
until a capacity of 1500 (Broca) is only 1409 (Schmidt), and one of 2000 (Broca) is 
1887 (Schmidt), the difference between the apparent and real capacities in the last 
example being as much as 1 1 3 cc. 
What is undoubtedly a desideratum in the determination of the cranial capacity is 
a method which will bring the two processes of guaging the skull and cubing its 
contents into precisely uniform conditions, so that the number obtained in the cubage may 
express the actual capacity. I have performed a number of experiments with this object, 
and have now elaborated a method which gives results so nearly uniform when tested 
with a standard skull, that it may, I think, be taken as furnishing in each case a close 
approximation to the actual capacity. This standard skull was itself prepared by 
stopping all the foramina, except the foramen magnum, with cement and by coating 
both the inner and outer tables with sealing wax varnish. The method is based upon 
two of the most important principles insisted on by Broca, viz., that the size of the 
particles employed must be uniform, and that they should be poured into the skull 
through a funnel, the neck of which has a definite diameter. 
No. 8 chilled shot has been employed as, from its hardness, it preserves its globular 
form much more efficiently than ordinary shot. 1 A litre is filled with this shot, which is 
then poured into the foramen magnum through a funnel 14*5 centimetres wide at the 
mouth, and 12*5 cm. in depth, the spout of which is 2 cm. long and 2 cm. wide. The 
skull is then lifted in both hands and a sharp tilt forwards given to it so as to project the 
shot into the anterior and middle cranial fossae. Shot is again poured in through the 
same funnel until it reaches the foramen magnum, care being taken that it shall pass 
well down into the occipital region. The skull is again lifted and a sharp tilt given, first 
1 I attach importance to the preservation of the globular form of the shot, as it thereby runs much more uniformly 
than if the particles were flattened or irregularly shaped. An objection to the method of ramming the shot employed 
by Broca is the constant change of form which the particles are made to undergo, and the alteration therefore in the 
number of their surfaces of contact. 
(ZOOL. CHALL. EXP. — PART XXIX. 1884.) Ff 2 
