CORRESP ONDENCE. 



26? 



CORRESPONDENCE. 



MISTAKES OF SCIENTIFIC MEN, ARTISTS, 

 AND POETS. 



Editor Popular Science Monthly : 



IN late numbers of this journal public 

 attention has been called to errors in the 

 statement of facts or of scientific points, by 

 men who should have known better. But 

 errors of the kind you name are not confined 

 to a few, but are found everywhere even 

 among poets and artists, as well as among 

 men of science. 



Some years ago a French artist was em- 

 ployed to paint a panel on the west wall of 

 the room belonging to a lodge. He made a 

 beautiful evening landscape, having the sun 

 in the horizon. A little above, and toward 

 one side, was the full moon. The shadows 

 of the trees in the foreground all pointed to 

 the moon as their source, although the whole 

 circle of the sun was still in view. I called 

 his attention to this want of conformity to 

 the facts but the picture was too good to 

 be spoiled by corrections ; so it remained as 

 it was made. 



There is a beautiful hymn by Seagrave, 

 found in many church collections, having a 

 part of a stanza as follows : 



"Rivers to the ocean ran, 



Nor stay in all their course ; 

 Fire, ascending, seeks the sun, 

 Both speed them to their source." 



[All the Italics in this letter are my own.] 

 The science contained in these lines is that 

 of the ancient heathen philosophy, viz., that 

 things heavy naturally tend downward, things 

 light naturally tend upward. 



The attribute of intelligence thus given 

 to the fire has but a sorry exemplification, 

 seeing that all fires which burn in the night 

 fail to get a right start in their search for 

 the sun. Of course, it is meant that the fire 

 goes upward of its own accord is not driven 

 by anything else. 



A distinguished professor of physics in 

 an Ohio college many years ago was accus- 

 tomed to say in his lectures that " hot air 

 rises, and the cold air rushes in to fill the 

 vacuum." I once called his attention to the 

 slip. He acknowledged the error and then 

 continued to speak as before, much after 

 the manner of the devil when he was sick 

 and wished to be a monk. 



The same absurd statement appears in 

 The Popular Science Monthly for last No- 

 vember, page 104, in the article on the origin 

 of The Mississippi Valley Rainfall. We find 

 as follows : " They [the winds] flow as on 

 an inclined plane, over the colder and more 

 dense air toward the north, and thus restore 

 the equilibrium of the atmosphere that has 



been disturbed. This disturbance is caused 

 by a continual flow of the cold and heavy 

 surface air from the extreme north toward 

 the equator, because along the tropical belt 

 a partial vacuum is created by the air becom- 

 ing heated and lighter, and in consequence 

 floating upward, and the cold air rushes in to 

 supply that vacuum.' 1 '' There it is. 



Again, in the February number of this 

 year, page 466, in the article on the Physical 

 Conditions of the Deep Sea, occurs this pas- 

 sage: "The particles of water thus heated 

 immediately commence to rise through the su- 

 perjacent layers of colder water, and the colder 

 particles would fall to take their places." 



On the principles of the ancient philoso- 

 phy these extracts are all right, but accord- 

 ing to the principles of modern physics they 

 are all wrong. Your own rebuke to such 

 carelessness was well deserved let us hope 

 that it may produce needed reformation. 



R. W. McFARLAND. 



COLUMBUS, OHIO, April 1, 1894. 



DO ANIMALS REASON? 



Editor Popular Science Monthly : 



THE February number of The Popular 

 Science Monthly has just arrived, and I 

 should like to add to the article on the Psy- 

 chology of a Dog two illustrations. 



When my father was in the navy during 

 the late war, his ship, the United States bark 

 Pursuit, lay at St. Joseph's Bay, Florida. 

 There was on board a dog (half pointer) 

 called " Secesh " because he had been cap- 

 tured from the " rebs." One day the men 

 went on shore, taking " Secesh " with them, 

 but when the time came to return the dog 

 was nowhere to be seen, and the men were 

 obliged to go back without him. Half an 

 hour later Secesh appeared upon the beach 

 and, finding the boat had gone, he started to 

 swim for the vessel ; but before he reached 

 it the tide caught him and was carrying him 

 rapidly out to sea ; he thereupon swam back 

 to the shore, trotted rapidly up the beach 

 for a considerable distance, and again struck 

 out for the ship, this time reaching it in 

 safety. 



Again : my grandmother was possessed of 

 a small dog of no particular breed. One 

 evening she, with my grandfather, was talk- 

 ing of going to visit her mother, some twenty 

 miles distant, on the following day. Dick, 

 the dog, lay on the hearth at their feet. My 

 grandmother remarked that they had better 

 shut Dick up before they started or he would 

 follow them. In the morning Dick was no- 

 where to be found, and they were obliged to 



