DIFFERENT KINDS OF EXERCISE. 137 



one of them. The particulars were furnished to me 

 by a young friend who was allowed to peruse the 

 manuscript of these pages, and who, as himself the 

 subject of the case, was struck with the perfect ac- 

 cordance between his own experience and the doc- 

 trines here expounded. It is proper to keep in view 

 that at the time of this experiment, my friend was 

 about seventeen years of age, and growing rapidly. 

 After having passed the winter, closely engaged in 

 a sedentary profession, and unaccustomed to much 

 exercise, he was induced by the beauty of returning 

 spring to dedicate a day to seeking enjoyment in a 

 country excursion ; and for that purpose set off one 

 morning in the month of May, without previous pre- 

 paration, to walk to Haddington by way of North 

 Berwick, a distance of thirty- four miles. Being at 

 the time entirely unacquainted with physiology, he 

 was not aware that the power of exerting the muscles 

 depended in any degree upon the previous mode of 

 life, but thought that if a man was once able to walk 

 thirty miles, he must necessarily continue to possess 

 the same power, under all circumstances, while 

 youth and health remained. The nervous stimulus 

 arising from his escape from the desk, and from the 

 expected delights of the excursion, carried him 

 briskly and pleasantly over the ground for the first 

 twelve miles, but then naturally began to decrease. 

 Unfortunately the next part of the road lay through 

 a dull, monotonous and sandy tract, presenting no 

 object of interest to the mind, and no variety of any 

 description ; so that the mental stimulus, already 

 greatly impaired in intensity, became still weaker. 

 Being alone, his intellect and feelings could not be 

 excited by the pleasures of companionship and con- 

 versation : weariness consequently increased at every 

 step; and long before his arrival at North Berwick 

 (twenty-five miles), " every vestige of enjoyment had 

 disappeared, time seemed to move at a marvellous 

 tardy pace> andevery mile appeared doubled in length.* 

 119 



