668 



SCIENCE. 



[N. S. Vol. XXI. No. 539. 



ter. The Chronicle refused to print it, but 

 offered to correct any misstatements in its 

 article, an illusory offer in relation to such a 

 tissue of inaccuracies, and one which we had 

 no desire to accept. 



We think it right that the scientific profes- 

 sions should know the attitude which the con- 

 ductors of some newspapers consider them- 

 selves justified in adopting towards scientific 

 workers, and we wish to record in your col- 

 umns, once for all, that protest which they 

 have not permitted us to make in theirs. 



G. N. Stewart, 

 C. C. Guthrie. 



Chicago, April 3, 1905. 

 Sir: — In yesterday's issue of your paper there 

 occurs a garbled and misleading account of cer- 

 tain experiments communicated by us to a meet- 

 ing of physiologists of the central states. We 

 are entirely opposed to the discussion of such 

 matters in the lay press. If any reporter was 

 present at our meeting he certainly was there 

 without invitation or permission. We do not 

 know from what source this remarkable piece of 

 copy reached your oiiice. But we can not think 

 the writer has fully considered how injurious 

 such notices may be to the reputation of scien- 

 tific investigators; and while we entertain the 

 greatest respect for your paper in its proper 

 sphere, we must beg of you in the future to do 

 us the honor of leaving us and our work alone. 

 We trust that you will give this letter the same 

 publicity as the paragraph to which we object. 

 We remain, yours truly, 



(Signed) G. N. Stewart, 

 C. C. Guthrie. 



A modest student of animal psychology. 



In the preface to ' The Watchers of the 

 Trails ' its author, C. G. D. Roberts, writes : 



The psychological processes of the animals are 

 so simple, so obvious, in comparison with those of 

 man, their actions flow so directly from their 

 springs of impulse, that it is, as a rule, an easy 

 matter to infer the motives which are at any one 

 moment impelling them. In my desire to avoid 

 alike the melodramatic, the visionary and the 

 sentimental, I have studied to keep well within 

 the limits of safe inference. Where I may have 

 seemed to state too confidently the motives under- 

 lying the special action of this or that animal, 

 it will usually be found that the action itself is 



very fully presented; and it will, I think, be fur- 

 ther found that the motive which I have here as- 

 sumed affords the most reasonable, if not the 

 only reasonable, explanation of that action. 



On page 221 of the same book the author 

 writes : 



As the raccoons crept along behind the wood- 

 shed they smelt traces of a sickly pungent odour, 

 and knew that other marauders had been on the 

 ground not very long before. Tliis made them 

 bolder in their enterprise, for they knew that 

 such depredations as they might commit would 

 be laid to the account of the skunks, and, there- 

 fore not likely to draw down vengeance upon the 

 [raccoon's] den in the sycamore. 



]\Iaynard M. Metcalf. 



The Woman's College of Baltimore, 

 March 19, 1905. 



A NEW FORM OF STEREOSCOPE. 



To THE Editor of Science : I read with in- 

 terest Professor Whitman's account of his 

 new form of stereoscope in your issue of April 

 7. I have described the same type of instru- 

 ment in Science, Vol. VII., p. 619. I was 

 led to the invention thereof by the instrument 

 called the perspectoscope which mistakenly 

 attempted to get a stereoscopic effect from a 

 single photograph, but in doing so used the 

 convenient device of placing the eyes at right 

 angles to the picture. Using this principle, I 

 made an apparatus with pivoting mirrors 

 which enabled me to throw one of a pair of 

 stereoscopic images into the one eye, and the 

 other into the other, just as Professor Whit- 

 man has independently done. I have used 

 this both in combination with weak lenses and 

 without them. I have had such an apparatus 

 in my laboratory for about seven years. 



The main advantage of the instrument (its 

 defects are well defined by Professor Whit- 

 man) for the psychological student is that it 

 offers a simple means of reversing the per- 

 spective without changing the card, throwing 

 the image of the right-hand picture into the 

 right or left eye and correspondingly for the 

 left eye, thus producing a stereoscopic or a 

 pseudoscopic effect; indeed, an intermediate 

 position in which the same view is thrown into 

 each eye is also possible and thus gives the 

 entire range of combinations. The Chicago 



