September 15, 1916] 



SCIENCE 



375 



died, when he was seventy-eight years old, 

 Professor Ludwig wrote to me to say that 

 he would take into his laboratory a young 

 American whom I had recommended. 

 Beginning the letter with a charming, 

 fanciful sketch of the way my new house 

 must look and the wish that he might be 

 there with us, he ran into a soberer vein 

 and wrote: 



Destiny has conferred on us professors the 

 favor of helping the responsive heart of youth to 

 find the right path. In the seemingly insignificant 

 vocation of the schoolmaster there is enclosed a 

 high, blessed calling. I know no higher. In its 

 fulfilment you will be the happier the more you 

 yourself grow in knowledge and power of thought, 

 the more you endeavor to be suited to the pro- 

 fession. How glad I am of your present and fu- 

 ture happiness. 



Ludwig died in his seventy-ninth year, 

 in Leipzig, April 27, 1895. His wife wrote 

 us: 



Our daughter had come to us to help care for 

 her father, and we were both by him day and 

 night. Seven weeks he lay sick, but his mind was 

 always clear. Only a few days before his death 

 his thoughts were busied with a paper which he 

 wished to write on his dead friend Helmholtz. 

 On the last evening he still asked us about many 

 things in which he was interested, then complained 

 of great fatigue and so softly slept. The hastily 

 called physician could only tell us that a sudden 

 heart failure had quickly and painlessly ended his 

 life. 



No better words can be spoken at the 

 end of an account of Ludwig 's life, than 

 those which he used at the close of his 

 Gedachtnissrede for Ernst Heinrich Weber : 



Now that he has departed from us, he has left 

 us a rich heritage, but inestimable good has sunk 

 into the grave with him. The one on whom his 

 soulful eyes rested, who listened to the flow of his 

 thoughtful words, who felt the pressure of his 

 hand, will always long for him. Yet not only the 

 friend, each one who in life and in science came 

 in contact with his power, will mourn the death of 

 a man, in whom were mingled in complete har- 



mony, a spirit as clear as his and a nature of such 

 richness. 



Warren P. Lombard 



University or Michigan, 

 Ann Arbor, Mich. 



ANIMAL LIFE AS AN ASSET OF 

 NATIONAL PARKS 1 



The argument most frequently urged in 

 favor of national parks is that they provide on 

 a large scale for the protection of forest areas, 

 and thereby ensure the transmission of a max- 

 imum water supply from the wooded tracts to 

 the needy lands below. Attention has also 

 been called to their value as refuges for wild 

 life — particularly where the animals to be con- 

 served are useful for game or food. Tbe strict 

 protection they afford enables the birds and 

 mammals within their boundaries to reproduce 

 at a maximum rate, and the surplus thus cre- 

 ated, spreading outwards into adjacent unpro- 

 tected areas, helps to make up for the deple- 

 tion caused tbere by excessive hunting. The 

 points mentioned above are fairly obvious. 

 But national parks have other less generally 

 recognized advantages, and among these we 

 consider their potential uses as places for rec- 

 reation and for the study of natural history, 

 especially worthy of notice. We will here lay 

 particular emphasis on their recreative value 

 because this phase seems to have hitherto been 

 treated only in a cursory way, and with an air 

 of hesitancy, as if it were hardly deserving of 

 practical consideration. 



The term recreation is currently applied to 

 any temporary change of occupation that calls 

 vigorously into play latent or seldom used fac- 

 ulties of the mind and body. It is the purpose 

 of this change to restore to the human organs 

 the normal balance which special or artificial 

 conditions of life disturb. As physiologists 

 have long recognized, the interdependence of 

 the various bodily functions is such that the 

 neglect of one is bound to have its effect on 

 the others, and complete health can only be 

 attained when every function is given its ade- 

 quate share of exercise. In view of this fact 



i Contribution from the Museum of Vertebrate 

 Zoology of the University of California. 



