194 
PROFESSOR KARL PEARSOK, MATHEMATICAL 
long bones of each kind, but it seemed worth while to measure dry and thoroughly 
humid a bone of each type. A bone of each type was placed at my disposal by 
Professor Thane, and they were measured independently on each occasion hy 
Mr. BPwiMLEY-M oore and myself. In the one or two instances in which we did not 
agree within ‘02 millim., the bone was again independently measured. Our results 
were as follows :— 
Table XI.—Lengths of Long Bones, Dry and Wet, in Centimetres. 
Dry as received. 
24 hour.s in water. 
120 hours in water. 
72 hours drying. 
F. 
42-58 
42-79 
42-84 
42-50 
T. 
37-41 
37-52 
37-58 
37-37 
H. 
34-.52 
34-62 
34-65 
34-48 
R. 
23-11 
23-20 
23-19 
23-00 
The bones themselves were between 200 and 300 years old.* They were only 
allowed to stand two hours for the water to run off before they were measured after 
soaking. In the case of the final 72 hours’ drying, it concluded with six hours in the 
neighbourhood of a stove. The first column may be considered to represent the 
average humidity of bones jareserved in a museum ; the last column complete dryness. 
It seems to me that the difference betv/een the first and third column is what we in 
general have to deal with. In this case we have a difference of 
F. T. H. E. 
2’6 millims. 1’7 millims. 1'3 millims. '7 millim. 
between dry and humid bones. 
The difierence between this result for the femur and Broca’s is very considerable. 
I think it is due to the fact that he allowed his bones to dry for 24 hours in a room 
before measuring them. I was much impressed by the rapidity with which the bones 
dried, and their conditions, of course, are very unlike what they would be if containing 
or sLirrouiided by animal matter. It is clear that the extensions due to humidity are 
not by any means proportional to the length of the hone, and it would he quite futile 
to attempt any percentage allowance for the extension due to this cause, the effect of 
which clearly differs with the different structure of different parts of the same hone. 
I have accordingly thought it best to subtract the above quantities from Eollet’s 
means, Mp, Mx, Mh, and Mr, and to consider the results so derived as giving the 
means of Eollet’s material on the supposition that the bones were dry and free from 
animal matter. Even so I do not think we shall err in over-estimating the difierence 
between the lengths of living and dead bone. Making allowances («) and (6) we 
have finally to subtract from PtOLLEx’s results for 
* See additional note, p. 244. 
