322 THE POPULAR SCIENCE MONTHLY. 



spring to the organs of locomotion, become less supple and more 

 attenuated, all of which contribute to the diminution of height. Car- 

 rying burdens on the head or shoulders leads to the same results. If 

 to an excessive fatigue is added privation of sleep, organic reparation 

 can not take place, and the causes which contribute to the diminution 

 of stature accumulate and effect in the total a decrease which is 

 relatively considerable. This fact is known to the tricksters who 

 practice upon young men liable to military service so as to secure 

 exemptions for them. If the men are only a few centimetres over the 

 minimum standard of the service, these practitioners put them through 

 a variety of fatiguing exercises, with carrying of burdens and priva- 

 tions, etc., till they succeed in reducing them below the minimum and 

 causing them to be rejected on examination. The same influence of 

 fatigue is also felt in ordinary life. The simple standing position, 

 walking, and riding, all contribute to a reduction of the height. We 

 are all taller in the morning than in the evening. Professor Martel 

 made a communication on this subject to the German Surgical Con- 

 gress held in Berlin in 1881, and presented a number of measurements, 

 from which he concluded that men's statures varied perceptibly ac- 

 cording to the hour of the day. The variation differs according to 

 occupations, being less in the case of those which are sedentary. 



The height of the adult continues stationary during mature age, 

 but begins to diminish at about fifty-five or sixty years. The decrease 

 is independent of the curvature of the vertebral column, and is ex- 

 hibited upon robust men who still hold themselves up straight. It 

 depends upon several causes, among which are a modification of the 

 neck of the femur, flattening of the fatty cushions, with gradual ossi- 

 fication and decrease in thickness of the cartilages of the joints, par- 

 ticularly of those of the vertebral column. 



Physical aptitudes are various according to stature ; and we are 

 able to draw important conclusions, particularly with reference to fit- 

 ness for military service, from the determination of them. The bodily 

 vivacity of small men is very much greater than that of large mem 

 The man of small stature is nearly always quicker and more alert than 

 a man who is tall and stout in proportion. This should be evident, for 

 such a man has less weight to displace when he is moving, jumping 

 or climbing; while it has been proved, by many experiments on animals, 

 that the strength does not increase in proportion to the weight. Two 

 horses weighing together three quarters of a ton can perform much 

 more work, particularly if it be work involving rapidity, than a single 

 horse having the same weight. A similar difference exists in the pow- 

 er of one large and stout man and two small men. The ratio of mus- 

 cular energy to the pound of living weight is much greater with small 

 or middling-sized men than with very large ones. The length of the 

 limbs of the latter necessarily occasions an amplitude in his motions 

 that makes execution slower. Length of limbs also contributes to a 



