548 PROCEEDINGS OF SECTION G. 
Nasal Obstruction and Mouth Breathing.—A very large 
proportion of the children examined, especially up to 10 
or 11 years, have been found to be suffermg from post 
nasal adenoid vegetations, and enlarged tonsils. Statistics 
have been collected, and, in several cases at least, as the 
result of a message to the parents, the children have been 
operated on with very beneficial results. The same remark 
applies to children, myopic and astigmatic, who now wear 
glasses correcting their errors of refraction. A large 
number also suffer from headache without any obvious 
cause, but this may be due in some cases to eye strain. 
PuysicaL MEASUREMENTS. 
The following is a brief account of the various measure- 
ments taken and recorded on the back of the Census 
cards. The instruments used are the Head Square, Cal- 
lipers, and Centimetre Tape, while the vertical heights are 
measured by the Anthropometer. 
MEASUREMENTS AND ANATOMICAL POINTS. 
The Head.— 
The Antero Posterior Diameter is taken from the most 
prominent part of the forehead to the external occipital 
protuberance, care being taken to hold the cephalometer 
horizontally. 
The Transverse Diameter is greatest width of head 
above the ears. 
Horizontal Circumference is taken with the tape from 
level of eyebrows over the occipital protuberance. 
Nasio Iniac Arc is the length over the head from the 
two points just mentioned. 
The Height of the Head is the distance from the chin 
to the vertex (head horizontal) taken with Anthropo- 
meter. 
Face.— 
The Length of Face is distance from the naso-frontal 
suture (root of nose) to point of chin. 
Bizygomatic Breadth is greatest width of face in front 
of the ears (horizontally). 
Interocular Breadth, taken by callipers, is distance 
between internal angles of the eyes. 
