578 THE POPULAR SCIENCE MONTHLY. 



of a distinguished physician : The head of a family having been struck 

 down by serious illness, this physician was called in to consult with 

 the ordinary medical attendant ; and, after examining the patient and 

 conferring with his colleague, he went into the sitting-room where the 

 family were waiting in anxious expectation for his judgment on the 

 case. This he delivered in the cautious form which wise experience 

 dictated : " The patient's condition is very critical, but I see no reason 

 why he should not recover." One of the daughters screamed, " Dr. 



says papa will die ! " another cried out, in a jubilant tone, " Dr. 



says papa will get well." If no explanation had been given, the 



two ladies would have reported the physician's verdict in precisely 

 opposite terms, one being under the influence of fear, the other of 

 hope. 



I shall now give a few illustrative examples, from recent experi- 

 ences, of the contrast between the two views taken of the same phe- 

 nomena (1) by such as are led by their " prepossessions " at once to 

 attribute to " occult " influences what they cannot otherwise explain, 

 and (2) by those who, under the guidance of trained and organized 

 common-sense, apply themselves, in the first*instance, to determine 

 whether there be any thing in these phenomena which "natural" 

 agencies are not competent to account for : 



1. When, in 1853, the " table-turning " epidemic had taken so strong a hold 

 of the public mind that Prof. Faraday found himself called upon to explain its 

 supposed mystery, he devised a very simple piece of apparatus for testing the 

 fundamental question, whether there is any evidence that the movements of the 

 table are due to any thing else than the muscular action of the performers who 

 place their hands upon it. And having demonstrated by its means (1) that the 

 table never went round unless the "indicator" showed that lateral pressure had 

 been exerted in the direction of the movement, while (2) it always did go round 

 when the "indicator" showed that such lateral pressure was adequately exert- 

 ed, he at once saw that the phenomenon was only another manifestation of the 

 involuntary " ideo-motor" action which had been previously formulated, on oth- 

 er grounds, as a definite physiological principle ; and that there was, therefore, 

 not the least evidence of any other agency. Yet it is still asserted that the 

 validity of Faraday's test is completely disproved by the conviction of the per- 

 formers that they do not exert any such agency ; all that this proves being that 

 they are not conscious of such exertion which, to the physiologist, affords no 



.proof whatever that they are not making it. 



2. So, again. Profs. Chevreul and Biot, masters of experimental science wor- 

 thy to be placed in the same rank with Faraday, had been previously applying 

 the same principles and methods to the systematic investigation of the phenomena 

 of the divining-rod and the oscillations of suspended buttons ; the former of which 

 were supposed to depend upon some " occult " power on the part of the perform- 

 er, while the latter were attributed to an hypothetical " odylic " force. And they 

 conclusively proved that in both cases the results are brought about (as in table- 

 turning) by the involuntary action of mental expectancy on the muscles of the 

 performer ; the phenomena either not occurring at all, or having no constancy 

 whatever, when he neither knows nor guesses what to expect, The following 



