264 



SCIENCE 



[Vol. LV, No. 1419 



These colors appear to be eharacteristie inter- 

 ference effects. Stoneyi describes almost iden- 

 tical phenomena and states the conditions under 

 which there would be formed crystals of such 

 orientation and thickness that light reflected to 

 the observer from the front and back surfaces 

 of the crystal would produce interference. The 

 explanation based on diffraction which McCon- 

 neV offers in criticism of Stoney's article does 

 not seem to fit the phenomena observed here. 

 His theory does satisfactorily explain the effects 

 which he observed during a winter spent where 

 similar phenomena were frequent, but there 

 the brightest colors were within a range of 

 from 3° to 7° from the sun and the farthest 

 distance at which he could ever detect any color 

 was 23°. He says that according to Stoney's 

 theory the most brilliant effects might reason- 

 ably be expected somewhere about 20°-30° from 

 the sun "for which we should look in vain." 

 There were in this case few if any iridescent 

 colors within the area where he found them 

 most brilliant, and certainly beyond 23° they 

 were very brilliant. It would therefore appear 

 that there are these two different types of 

 phenomenon. 



Mabel A. Chase 

 Mount Holtoke College, 



South Hadley, Mass. 



QUOTATIONS 



THE PROPOSED SUPPRESSION OF THE 



TEACHING OF EVOLUTIONi 



The mode of origin of species was prac- 

 tically discovered by a little-known German 

 paleontologist by the name of Waagen in 1869, 

 but, like the great discovery of Mendel in 

 heredity, this truth has been long in making 

 its way, even among biologists. Waagen's ob- 

 servations that species do not originate by 

 chance or by accident, as Darwin at one time 

 supposed, but through a continuous and well- 

 ordered process, has since been confirmed by 

 an overwhelming volume of testimony, so that 



1 Phil. Mag., a. 5, Vol. 24, p. 87. 



2 Phil. Mag., a. 5, Vol. 24, p. 423. 



1 Extracts from articles in the New York Times 

 for March 5, in answer to the article by Mr. 

 Bryan from which extracts were printed in the 

 last issue of Science. 



we are now able to asemble and place in order 

 line after line of animals in their true evolu- 

 tionary succession, extending, in the ease of 

 what I have called the edition de luxe of the 

 horses, over millions of years. We speak to the 

 earth from Eocene times onward to the closing 

 age of man, and it always teaches us exactly 

 the same story. These facts are so well known 

 and make up such an army of evidence, that 

 they form the chief foundation of the statement 

 that evolution has long since passed out of tho 

 domain of hypothesis and theory, to which Mr. 

 Bryan refers, into the domain of natural law. 



Evolution takes its place with the gravita- 

 tion law of Newton. It should be taught in 

 our schools simply as Nature speaks to us 

 about it, and entirely separated from the opin- 

 ions, materialistic or theistic, which have clus- 

 tered about it. This simple, direct teaching of 

 Nature is full of moral and spiritual force, it 

 we keep the element of human opinion out of it. 

 The moral principle inherent in evolution is 

 that nothing can be gained in this world with- 

 out an effort; the ethical principle inherent in 

 evolution is that the best only has the right 

 to survive; the spiritual principle in evolution 

 is the evidence of beauty, of order, and of de- 

 sign in the daily myriad of miracles to which 

 we owe our existence. This is my answer to 

 Mr. Bryan's very natural solicitude about the 

 influence of evolution in our schools and col- 

 leges — a solicitude not inherent in the subject 

 itself, but in the foolishness and conceit of 

 certain of the teachers who are privileged to 

 teach of the processes of life. 



It would not be true to say that the evolution 

 of man rests upon evidence as complete as 

 that of the horse, for example, because we have 

 only traced man's ancestors back for a period 

 of 400,000 years, as geologic time was con- 

 sei-vatively estimated in 1893 by Secretary 

 Waleott of the Smithsonian Institution, Wash- 

 ington ; whereas, we have traced the horse back 

 for a period of 3,000,000 years, according to 

 similar estimates of geologic time. 



The very recent discovery of Tertiary man, 

 which I have just described in Natural History 

 (November-December, 1921), living long be- 

 fore the Ice Age, certainly capable of walking 

 in an erect position, having a hand and a foot 

 fashioned like our own, also a brain of suffi- 



