210 



The Journal of Heredity 



inferior. The theory thus falls to the 

 ground, in the opinion of n^any, from 

 lack of proof. 



With the desire to test the theory by 

 a method whieh would obviate the ob- 

 jections raised against that of Pearson 

 and his co-workers, I investigated the 

 records of the physical examinations of 

 students who have entered Amherst 

 College for a number of years past. At 

 this institution Dr. Edward Hitchcock 

 was the first man in charge of a collegiate 

 physical department in America to 

 establish anthropometric measurements 

 and strength tests. He worked out a 

 system of examination which was so 

 thorough that there has been found no 

 reason for changing the tests in more 

 than 40 years. Each incoming freshman 

 class has been measured and tested in 

 the same way during all that time. 



Thus a disinterested and reliable 

 means of making an investigation as to 

 the comparative strength of brothers 

 was furnished ; and as all those included 

 in the data are adults, to the extent at 

 least of being old enough to enter college, 

 the fallacy pointed out by Macaulay in 

 Pearson's studies is here obviated. 



With the cooperation of Amherst 

 authorities, I secured a list of 58 sets of 

 brothers, from the physical examination 

 charts. A correspondence was conducted 

 with these individuals, particularly with 

 a view to learning the ages of their 

 parents, and their own order in the 

 fraternities. Some of these sets of 

 brothers included three individuals; 

 most of them only two. Some of the 

 sets I was obliged to disregard, in var- 

 ious computations, for various reasons. 



In grouping the records of strength 

 tests, I found first-born brothers strong- 

 est in four cases, second-born brothers 

 strongest in 12 cases, and third-boni 

 strongest in 28 cases. As the individuals 

 concerned came to college at about 

 the same age, on the average, it seems 

 clear enough that first-born brothers 

 who came to Amherst were weaker 

 than their younger brothers who fol- 

 lowed. 



HandHng the figures in a different 

 way, it was found that first-bom brothers 

 made a total of 11,361 ])oints in the 

 strength tests, second ])orn had 12,510, 



and third born 13,251. The average 

 strength of each individual in each 

 class was: first bom, 494 points; second 

 bom, 544 points; third bom, 576 jioints. 

 Of course, with such a small group of 

 men, a few exceptional individuals 

 would make a considerable change in 

 the totals, and we know that there were 

 exceptional individuals. Nevertheless, 

 the results are so consistent as to make 

 me confident that in this case the com- 

 parative strength of the brothers is 

 faithfully represented by these figures, 

 which seem to indicate that second- 

 born sons were about one-tenth stronger 

 than first-bom sons, and that third- 

 born sons were correspondingly stronger 

 still. 



Out of all the records taken, there 

 were only 20 boys who made more than 

 600 points in the strength test on their 

 entrance to the college, while there were 

 onl)' 14 who were below 450. Suppose, 

 then, we say that those below the 450 

 mark are weaklings, those about 525 

 normal, and those above 600 strong. 

 This makes 75 points as the difference 

 between a normal young man and a 

 weakling on one side, and an exception- 

 ally strong man on the other side. 



And this is just about the difference 

 in the average strength of the first- 

 born and third-born sons who entered 

 Amherst College. 



Taking only the two older of each 

 of these sets of brothers, I added three 

 more similar pairs for which the same 

 data were available, and tested them 

 on height and weight, as well as strength. 

 Without going into details, I give the 

 results : 



Younger brothers were heavier in 24 

 cases; older brothers were heavier in 

 23 cases. 



Younger l)r(jthers were taller in 22 

 cases; older brothers were taller in 25 

 cases. 



Younger Ijrothers were stronger in 30 

 cases; older brothers were stronger in 

 17 cases. 



The interi)retation of these results 

 may afford room for some dispute; but 

 as the disparity in strength is still 

 marked, it seems to me merely to indi- 

 cate that height and weight have little 

 bearing on the question of strength or 



