ntary school pupils that of 1,649 pupils
losing four weeks or more in a single year 459 belonged to the
accelerate pupils, 647 to those arrested, and 543 to pupils normal in
their school work. He accredits such large loss of time as almost
invariably the result of illness and of contagious disease. He also
says, "Prolonged absence from school is appreciable in producing
arrest especially when it amounts to more than 25 days in one school
year." But the diseases of childhood, with the resultant absence, are
less prevalent in the high school years than earlier. Furthermore, the
losses due to change of residence will not be met with here, for, as
explained in Chapter I, no transferred pupils are included subsequent
to the time of the transference either to or from the school.

The influence of physical or mental defects also deserves recognition
here as a possible factor relative to school failures, although this
study has no data to offer of any statistical value in that regard. A
few pupils in high school may actually reach the limits prescribed by
their 'intelligence quotient'[15] or general mental ability, or
perhaps, as Bronner[16] so interestingly points out, be handicapped by
some special mental disability. If such be true, they will doubtless be
found in the number of school drop-outs later referred to as failing in
50 per cent or more of their work; but we have no measurement of
intelligence recorded for them to serve our purposes of
prognostication. In the matter of physical defects alone, the report of
Dr. L.P. Ayres[17] on a study of 3,304 pupils, ten to fourteen years
old, in New York City, states that "In every case except in that of
vision the children rated as 'dull' are found to be suffering from
physical defects to a greater degree than 'normal' or 'bright'
children." The defects of vision, which is the exception noted, may be
even partly the result of the studious habits of the pupils.
Bronner[16] remarks on the "relationships between mental and physical
conditions," and also on how "the findings on tests were altogether
different after the child had been built up physically." But Gulick and
Ayres[18] conclude that it is evident from the facts at hand that if
vision were omitted the percentage of defects would dwindle and become
comparatively small among the upper grades. This would probably be
still more true for the high school; but this whole field has not yet
been completely and thoroughly investigat