ON THE INFLUENCE OF SOHOOL-BOOKS UPON EYESIGHT. 297 
to their possible effects on eyesight, but without formulating any 
definite rules. Several state that the Committee or officers responsible 
for the supervision of the book-supply pay attention to the type, 
paper, &c.; several, on the other hand, inform us that the selection 
of books, &c., is left to the teachers. 
Summarising the evidence generally, it may be said that whilst 
effective arrangements for the detection of existing defects in the 
eyesight of elementary school children are general and arrangements 
for the supply of proper spectacles at cheap rates are not uncommon, 
practically no systematic attention is given to the influence of school- 
books upon eyesight. 
The replies lead us to believe that the report of the Committee wil 
have attention from Local Education Authorities, : 
Report of the Oculist Sub-Committee. 
The eye of the child is a growing eye. It is immature both in 
structure and in function. At birth the eye has a volume equal to 
about half that of the full-grown eye; the materials of which it is built 
are comparatively soft and yielding; the functional power of the visual 
apparatus is merely a perception of light. By growth and develop- 
ment, rapid at first, slower later on, the eye tends progressively to 
acquire the dimensions and the powers of the normal completed organ. 
Nutrition by healthy blood, and the natural stimulus of volun- 
tary use, are essential to this process. We know by experience that 
in early infancy disease may arrest the growth of the eye, and that 
suspension of use, as when a serious ophthalmia prevents an infant 
for many weeks from attempting to use its eyes, may check func- 
tional development to an extent which cannot afterwards be made 
good. On the other hand, excessive efforts, due to unnatural demands 
on the eyesight, are apt to be injurious in the opposite direction. 
Unfortunately there is evidence to show that the demand made on 
the eyesight of school children is not infrequently excessive. 
At the age when school life begins the visual apparatus is still 
immature. The orbits, the eyes themselves, and the muscles and 
nerves which move them, have still to increase considerably in size. 
The various brain-structures concerned in vision have not only to grow 
but to become more complex. The intricate co-ordinating mechanism 
which later will enable the eyes, brain, and hand to work together 
with minute precision, is awaiting development by training. The 
acuteness of vision is still below the standard proper to the 
finished eye. The refraction of the eyes is not yet fixed. It is usually 
more or less hypermetropic, with a tendency to change in the direction 
of normal sight; in other words, it has not reached the ideal condition 
in which the eyes see distant objects without accommodative effort, 
but is tending towards it. In short, the whole visual apparatus is still 
unfinished, and is therefore more liable than at a later age to injury by 
over-use. 
Over-use of the eyes is chiefly to be feared in such occupations as 
reading, writing, and sewing, not in viewing distant objects. During 
near work the head is usually bent forward, and the blood-vessels of 
