NOVEMBEE 12, 1920] 



SCIENCE 



467 



of 84 cents a page. In addition lie is a 

 subscrilber to the Journal at $6.50 a year. 



In contrast we see that the "popular" 

 magazines flourish as never before and pub- 

 lish beautiful color illustrations galore. We 

 are told that scientific periodicals can not 

 have these things because they don't pay." 

 We wonder, Does not science pay to-day as 

 well as in 1917? Will it "pay" to let the 

 scientific world send to Leipzig for its period- 

 icals, rather than to Baltimore? 



If scientific publications are to survive and 

 if this country is to support scientific work 

 as it supports other things, there must be 

 some form of endowment for that purpose. 

 Corporations and individuals whose business 

 is even remotely connected with the results of 

 scientific work will find it a good investment 

 in years to come. 



The scientists are willing, and do, bear 

 more than their share of the expense of their 

 publications, but outside help is necessary. 

 These periodicals can not exx)ect to pay 

 dividends to the publisher because they are 

 xmattractive to advertisers as a class. The 

 technical and scientific periodicals need en- 

 dowments sufficient to allow them to present 

 adequately the results of research and to 

 enable them to circulate at a subscription 

 price low enough to enable all workers and 

 libraries to buy them. 



Howard S. Eeed 



Citrus Experiment Station, 

 EiVEBSiDE, California 



ROAD REFLECTIONS 



To THE Editor of Science : Eeferring again 

 to the subject of road reflections, Mr. Freemen 

 F. Burr in Science for September 24 notes 

 having observed reflections occurring at con- 

 siderable heights above the surface of the 

 road. I have made thousands of careful ob- 

 servations of this phenomenon and have found 

 that the reflecting surface always coincides 

 with the road surface as closely as the eye 

 can determine. 



Since the true surface disappears when a 

 reflection takes place there is often an appear- 

 ance of shifting which careful observation 



shows to be illusory. Thus a reflecting sur- 

 face on the top of a hill sometimes seems at a 

 casual glance to be several inches from the 

 road and seems to hide objects beyond. In 

 every such case the hill itself is what cuts off 

 the vision. 



I have observed the reflections many times 

 under circumstances that preclude entirely 

 the ascribing of them to warm layers of air. I 

 have seen them on cloudy days, on shaded 

 stretches of road and in one place where a 

 white sign-board furnishes a convenient back- 

 ground a very striking reflection may be seen 

 long after sunset. 



To be sure they are much more in evidence 

 on bright days than on dull days, but since 

 they appear even more brilliantly on a very 

 cold bright winter day with snow on the 

 ground than on a warm summer day the con- 

 clusion to be drawn is that the contrast of 

 bright colors throws the reflections into more 

 prominent relief on sunny days. 



The same phenomenon may be observed by 

 holding any smooth normally non-reflecting 

 surface, such as that of tarnished metal or of 

 a smooth whetstone, at a small angle to the 

 line of vision. Objects beyond appear bril- 

 liantly reflected as if in a mirror. 



It may be that in some instances a thin air 

 layer immediately adjacent the surface aids 

 by bending some incident rays so that they 

 strike within the critical reflection angle. 

 But the air layer certainly is never primarily 

 responsible for reflections of this kind. 



H. H. Platt 



SCABSDALE, N. Y. 



THE INFLUENCE OF FRESH FOOD IN 

 LACTATION 



The suggestion of Hart, Steenbock and 

 Hoppert, in the Octdber 1 number of this 

 journal, that a vitamine in fresh grass favor- 

 ably influences calciiun metabolism is a step 

 in a direction in which, I am convinced, im- 

 portant progress is to be made. 



Through extensive investigations on the 

 mineral metabolism of farm animals I had 

 reached a hypothesis identical with the pro- 

 visional conclusion of Hart and associates. 



