104 LABORATORY MANUAL OF ANTHROPOMETRY 



table, with the bicipital tuberosity looking straight upwards, there will 

 be seen considerable difference in the angle which this distal line makes 

 with the plane of the table. In other words the angle made between this 

 line and one at the proximal end driven straight down through the tuber- 

 osity is subject to much variation. This angle is called, 



11. Angle of torsion. It is measured by the parallelograph, which 

 places on a piece of paper placed on the table a projection of the two 

 lines involved, in the case of a bone held in a clamp and placed perpen- 

 dicularly over the table. The angle is then determined by the transparent 

 protractor. 



Viewed in another way this measurement defines precisely the direct- 

 ion towards which the tuberosity points when the bone is placed in the 

 volar plane. If in this position the tuberosity points directly upwards, 

 its axis is at right angles to that of the distal articular surface line and the 

 angle is 90; if it point laterally, along the crest, its axis lies in the volar 

 plane and the angle is 0. This is about the condition in the large apes, 

 and in the Neandertal species of man; indeed, occasionally in an ape 

 (apparently always in the chimpanzee) the tuberosity axis passes the 

 line, that is, the volar plane, and actually faces a little backwards, making 

 a minus angle. In the white race in general the angle is somewhere 

 around 45, and consequently looks obliquely forwards and inwards. 



The following results of the study of this angle have been found by 

 Fischer, who, however, uses the complement of the angle as described 

 here, considering the position in which the tuberosity looks directly up- 

 wards as 0, and that in which it lies in the volar plane as 90. The table 

 here, in order to agree with the textual explanation has been translated 

 into the complements of Fischer's table. 



TABLE SHOWING THE ANGLE OF TORSION 



Simian apes 



Chimpanzee 3.5 



Gibbon +0.5 



Gorilla 2.0 



Orang-utan 5.8 



Homo neandertalensis 



Neandertal specimen 2.0 



Spy -. 9.0 



Homo sapiens 



Hawaiians 23 . 



Melanesians 24 . 7 



Australians 26 . 3 



Negroes 26.7 



Fuegians 29 . 5 



Burmese 31.6 



Veddah 37 . 



Negritoes 37.5 



South Germans (Baden) 39.8 



Lake-dweller pygmies (prehist) 49 . 2 



