September 15, 1916] 



SCIENCE 



377 



sity in adapting the parks for recreative pur- 

 poses is to preserve natural conditions. In 

 this respect a national and a city park are 

 wholly different. A city park is of necessity 

 artificial, in the heginning at least when the 

 landscape is planned and laid out; but a na- 

 tional park is at its inception entirely natural, 

 and is generally thereafter kept fairly immune 

 from human interference. Herein lies the fea- 

 ture of supreme value in national parks: they 

 furnish samples of the earth as it was before 

 the advent of the white man. Accordingly, 

 they should be left in their pristine condition 

 as far as is compatible with the convenience of 

 visitors. All necessary roads, trails, hotels and 

 camps should be rendered inconspicuous, or, 

 better still, invisible from the natural points of 

 vantage in the parks. Another reason for re- 

 taining primitive conditions is that natural 

 scenery unmarred by man is one of the finest 

 known sources of esthetic pleasure. Any at- 

 tempt to modify the appearance of a national 

 park by laying out straight roads, constructing 

 artificial lakes, trimming trees, clearing brush, 

 draining marshes, or other such devices, is in 

 the worst of bad taste. 



As has already been intimated, the animal 

 life of the parks is among their best recreative 

 assets. The birds and mammals, large and 

 small, the butterflies and the numerous other 

 insects, even the reptiles and amphibians, are 

 of interest to the visitor. As a stimulant to 

 the senses of far sight and far hearing, facul- 

 ties largely or altogether neglected in the pres- 

 ent scheme of civilization, they are of no less 

 consequence than the scenery, the solitude and 

 the trails. To the natural charm of the land- 

 scape they add the witchery of movement. As 

 soon as the general surroundings lose their 

 novelty for the observer, any moving object in 

 the landscape will catch his eye and fix his at- 

 tention. People will walk miles and climb 

 thousands of feet to secure a good view of fall- 

 ing water, and this desire for movement is 

 even more completely satisfied by the sight of 

 animals in motion. The moving deer, passing 

 within range of the stage-coach, rouses excla- 

 mations of surprise and delight. Eagles and 

 pigeons in flight overhead readily claim the 



traveler's notice, and the smaller birds often 

 mingle the fascination of sprightly movement 

 with that of bright color and pleasing song. 

 Considering the predilections of the average 

 visitor, we should perhaps regard these last as 

 the most indispensable creatures in the parks. 



The interest of moving objects depends upon 

 a number of elements other than movement, 

 among which their color, and especially their 

 size, is important. The chipmunk is more at- 

 tractive than the ground squirrel, primarily 

 because its movements are more rapid, and 

 secondly because of its more brightly colored 

 markings. But when movement and color are 

 equal the average observer's selection seems to 

 have a quantitative basis, though the rarity of 

 the object, and its romantic or other associa- 

 tions affect the equation. A bear or a deer 

 will elicit more interest than a smaller mam- 

 mal, even though the latter be of a rarer spe- 

 cies. There are exceptional cases where an' 

 animal's extreme rarity will make it of excep- 

 tional interest in spite of its inferior size, but 

 in general the larger species are the more 

 rare, as they are the first to disappear before 

 human invasion. They have therefore a 

 double claim to consideration, and measures 

 should be taken to prevent their numbers 

 from diminishing. After the visitor's initial 

 curiosity has been aroused and his powers of 

 observation developed, he may be trusted to 

 give a closer study to the smaller species. 



To realize the greatest profit, therefore, 

 from the plant and animal life of the parks, 

 their original balance should be maintained. 

 No trees, whether living or dead, should be 

 cut down, beyond those needed for building 

 roads, or for practical elimination of danger 

 from fire. The use of wood for fuel in power 

 stations, or even for cooking and heating in 

 hotels and camps, is made unnecessary by the 

 abundant supply of water power everywhere 

 available, and this may be utilized without 

 marring the scenery in the slightest. Dead 

 trees are in many respects as useful as living, 

 and should be just as rigorously protected. 

 The brilliant-hued woodpeckers that render 

 such effective service in ridding the living 

 trees of destructive insects depend in part on 



