350 AVERAGE WEIGHT OF THE BRAIN IN THE 



in the order in which they have been here placed, — the only change being that shot 

 came before peas ; that is to say, that the range of variation among the eight 

 measurements with shot was only five cubic centimetres, with peas only eight c.c, 

 but with the other substances, in an ascending degree until it amounted to sixty c.c, 

 with fine sand. This might, at first view, be supposed to prove that there is con- 

 siderably more difficulty in gauging skulls with sand in a uniform manner than with 

 any of the other substances named. But it must not be overlooked that in the 

 measurements of the different substances employed, subsequently to the gaugings. Dr. 

 "Wyman poured them into his measure at a uniform rate, but without shaking or 

 pressing them down. The shot, and even the peas, would gravitate at once nearly 

 to their definite volume. The coarse sand, but especially the fine sand, would 

 envelope and carry down much air, and would, from the irregularity of size and fox-m 

 of their particles, absolutely require to be shaken down well, in order to regain the 

 same volume they occupied in the cranium. Px-of. Wyman does not mamtain that 

 observations made with dry Calais sand are vitiated by the results of his experiments, 

 only that the use of a substance the particles (if which are definitely spherical, and of 

 the same size and weight, is to be preferred for gauging skulls. He candidly admits 

 that, " with proper care, correct measurements can of course be made with either of 

 the materials mentioned in the table, and, in practice, no one would omit to shake 

 down and compress the material in the measure to the same degree that he would in 

 the skull." It may reasonably be concluded that where the capacity is obtained by 

 the same hands, with the same sand, and by a uniform method of manipulation, the 

 chances of variation are much lessened ; and the data upon which the following 

 tables are constructed may be regarded as sufficiently accurate and trustworty. 



There is, however, another point, which seems as if proved by Dr. Wyman's experi- 

 ments, that may deserve to receive our attention. The average capacities obtained 

 by the seven different matters were very different, or, at least, appeared to be very 

 different. This is what might have been expected to be the consequence of the fine- 

 ness or coarseness of the particles influencing their penetrability, which would also 

 be modified by the weight of the substance employed. The measures of the different 

 substances used rise gradually from the peas to the fine sand, in the order in which 

 they are given above; and the increase itself ascends from peas 1193 c.c. to fine sand 

 1313 c.c, apparently showing that the latter fills the cranial cavity more thoroughly 

 than any of the other substances, and approaches in this" respect to water in being 

 adapted to gauging this cavity. "Water, which has been used by some for this pur- 

 pose, — by Prof. John Marshall, for instance, — it is said by Prof Wyman " would un- 

 questionably be the best." The fact that on an average 1313 c.c. of fine sand can be 

 got into a skull which is usually filled with 1193 c.c. of peas, or 120 c.c. less, inde- 

 pendently of its influence upon the question of which is the best material for use in 



