RT Journal
A1 MACDONALD A
T1 Colored children: A psychophysical study.
JF Journal of the American Medical Association
JO Journal of the American Medical Association
YR 1899
FD May 27
VO XXXII
IS 21
SP 1140
OP 1144
DO 10.1001/jama.1899.92450480001002
UL http://dx.doi.org/10.1001/jama.1899.92450480001002
AB In all new lines of inquiry it is a general principle to regard the results as more or less tentative, according to the number of persons experimented upon.In this study the results depend upon averages which are valuable according to the whole numbers from which the averages are made. In many instances these numbers are not as large as one would desire. We hope this may induce some investigator to make experiments upon larger numbers.SPECIAL STUDY OF NINETY-ONE COLORED CHILDREN. 
    Instruments used: The calipers (Fig. 1) are used for measuring the length and width of head.The right end of the calipers (R) is held at the root of the nose; the one measuring watches the scale while he brings the left point of the calipers over the back and middle of the head, thus finding the maximum length of head. The width of the head is measured