500 
The Measurements of the Pelvis 
difficulty of putting the bones together on different occasions so as to get constant 
measurements is increased under the conditions of the experiment. After the 
bones have taken up water the shape of their articular surfaces is altered ; hence 
the bones do not fit together in quite the same way as they did before, and the 
measurements are not fully comparable. A difference in the tilt of the sacrum, 
for example, may affect the two conjugates and the antero-posterior diameter. 
But there is another difficulty. These old bones are very fragile and are apt 
to crack, as both hip bones did in this experiment. Flakes of bone come away 
from the surface. This happened at the upper part of the pubes in this pelvis, 
and is the reason why the record for the obstetric conjugate and pubic height 
is incomplete. Fortunately we were able to surmount these difficulties. 
Prof. Thane lent us two modern English pelves, one female and one male 
(previously referred to as IV and V respectively), with the bones still attached 
to each other by the ligaments. Both were measured in the dry state. Pelvis IV 
was measured after immersion in water for 22 and 68 hours, and subsequent drying 
for 39 days. Pelvis V was measured after 98 hours in water, and subsequent 
drying for 35 days. The final measurements were very nearly the same as the 
initial, so that the mean of the two was taken as a good measure of the diameters 
in the dry pelvis. In the case of the first pelvis (IV) the numbers after 22 and 
68 hours in water were also very close, and the mean of these was taken as the 
measurement in the moist state. The measurements in the dry state with their 
increase in the moist state are tabulated below. 
The negative sign in the fourth column indicates that moisture caused some 
diminution of the measurement in question. 
TABLE VII. 
Pelvis IV S 
Pelvis V rf 
Mean 
of 
Differences 
Dry 
Difference 
Dry 
Difference 
Inter-crests 
26-26 
•10 
26-54 
•18 
■14 
Inter-spines 
21-40 
•02 
23-29 
•04 
•03 
Transverse 
15-85 
•06 
11-63 
•08 
•07 
Diagonal conjugate ... 
14-14 
•15 
12-70 
•10 
•13 
Obstetric conjugate ... 
12-42 
•00 
10-32 
■02 
•01 
Antero-posterior 
10-11 
■13 
1071 
■03 
•08 
Pubic height ... 
3 72 
•22 
4-20 
•21 
•22 
Right hip — height 
19-03 
•07 
21-55 
•05 
•06 
„ ,, breadth ... 
15-78 
■06 
15-87 
- -07 
- -01 
Left hip — height 
18-79 
•11 
21-70 
•10 
11 
„ „ breadth 
15-77 
•05 
15-87 
•03 
•04 
The differences are small, the greatest being a little over 2 mm. for the pubic 
height. Moreover they are very close for the two pelves. The means of these 
