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Dr. E. W. A. Walker. 



the individual can by " sitting low " or " sitting high " produce at will a 

 variation of as much as 3 or more per cent. But, since a subject conscious 

 that he is being measured for height tends naturally to produce a full 

 measurement, it will be found that he intentionally " sits up," straightening 

 the spine, tilting the pelvis forward, and rests on the contracted muscles of 

 the thighs and buttocks instead of on his ischial tuberosities. The apparent 

 length — " sitting height," as it has been termed — is thus increased by between 

 2 and 3 per cent, above the measurement of length taken in the manner 

 already described. Accordingly measurements taken on a seat require to be 

 corrected down appropriately before they can be treated as comparable with 

 the measurement of body-length in infants or animals. 



In infants too young to sit the measurement of length is carried out as 

 follows. Two pairs of hands are required. A table is brought up against the 

 wall and the infant is laid upon the table on its back so that the head carefully 

 held in position just touches the wall. The pelvis is held down upon the 

 table, the thighs flexed on the trunk, and a vertical flat piece of board is 

 brought up against the nates. The distance between the board and the wall 

 gives the length of the body. 



Weight. — The weight of the body is, of course, the weight without clothes. 



Data and Calculations. 



The data employed in the present investigation consist in part of measure- 

 ments made by myself ; and in part of measurements kindly obtained for me 

 by Mr. G. Haynes at the Oxford Preparatory School; by Mr. Carter at the 

 New College (Oxford) Choir School ; and by Miss Poulton at Malvern College 

 for Girls. To each of them I am very greatly indebted for the care and 

 accuracy with which my directions for measurement were carried out. All 

 the measurements in infants and very young children, as well as some in 

 older children, were made by myself, Mr. Haynes supplied the data for 

 94 boys, Mr. Carter those for 19 boys, and Miss Poulton those for 56 girls. 



The subjects were all healthy normal individuals, well nourished and 

 living under favourable conditions. Their average weight and height for each 

 year of age are above those usually given in tables for the general 

 population. 



In addition to the data already mentioned I had at my disposal, by the 

 kindness of Dr. E. H. J. Schuster, measurements made by him on 1500 

 undergraduates at Oxford. 



These data have formed the basis of a series of calculations whose result 

 has been to show that the length of the body (stem-length) in man can 



