74 8 



THE POPULAR SCIENCE MONTHLY. 



we are now able to do indirectly, though 

 only by long and difficult processes of 

 investigation ? 



This is certainly a dictate of common- 

 sense. The test of clairvoyance is what 

 the alleged exceptional clearness shows. 

 The question is, Can the clairvoyant 

 actually do what he pretends to do? 

 And the proof is not the mere testimony 

 of a few parties, who say they have 

 seen extraordinary things, but what has 

 been positively, and demonstrably, and 

 openly gained to science ? This is the 

 test in the case of all other scientific 

 discoveries. M. Burdin, a member of 

 the Academy of Sciences, put the claims 

 of clairvoyance to very simple and de- 

 cisive proof in 1837, when the real 

 " evidence" signally failed. He placed 

 3,000 francs in the hands of a notary, 

 suhject to the order of the Academy, to 

 be given to any one who would read 

 writing placed in an opaque box, a 

 committee of the Academy being ap- 

 pointed to supervise the experiments. 

 The conditions were modified in vari- 

 ous ways to suit objectors, the only 

 point being to determine whether the 

 clairvoyant could actually see through 

 an opaque substance, and the time al- 

 lowed to find a party who could do this, 

 at first two years, was extended to three. 

 Numerous trials were made, but none 

 succeeded. The result, however, of the 

 carefully-conducted experiments was to 

 detect, in several instances, the fraudu- 

 lent mode in which the alleged previous 

 successes had been obtained. 



NEW SOLAR PHOTOGRAPHS. 



M. Janssen, the eminent director 

 of the observatory at Meudon (France), 

 has for some time been giving his at- 

 tention to solar photography, and with 

 singular success. The very remarkable 

 photographs he has lately produced 

 have hardly yet reached this country ; 

 but, from the examination of one, sent 

 by him to the Allegheny Observatory, 

 and which we have had the opportunity 



of seeing, we find that the praise be- 

 stowed abroad upon these new results 

 is fully deserved. 



The surface of the sun itself has 

 been described by recent observers as 

 consisting of a relatively dark back- 

 ground, thickly starred in every part 

 by those strange objects called techni- 

 cally "granules," or "rice-grains," and 

 which constitute the real source of the 

 solar light. These, which have hither- 

 to only occasionally been seen by good 

 telescopes, are now definitely fixed for 

 us by the camera, and we may see for 

 ourselves that they, with their sur- 

 rounding gray, do resemble to com- 

 pare great things with small rice in a 

 plate of soup, though the photograph 

 shows that they are not in general elon- 

 gated, but nearly round, with an ir- 

 regular outline, as described by careful 

 observers. We must leave, however, 

 to special students the study of these 

 details, and only observe that the pho- 

 tograph, besides confirming previous 

 optical observations as to the remark- 

 able fact that the light and heat of tho 

 sun come from but a small part of its 

 surface, adds otherwise directly to our 

 knowledge, by presenting new facts, 

 such as the evidence of storms upon 

 the solar surface (quite away from the 

 spots), which have never yet been dis- 

 tinctly observed by the telescope. 



These admirable photographs can 

 hardly fail to soon become known, by 

 copies to the scientific public, for they 

 constitute a most essential step in tho 

 study of the sun, and one on which M. 

 Janssen is certainly to be congratu- 

 lated. 



THE EDISON PHONOGRAPH. 



In a certain sense, this " acoustical 

 marvel of the century " is as simple as 

 a grindstone ; but, in a scientific point 

 of view, there are subtile questions 

 about it that only trained physicists can 

 appreciate. Prof. Mayer's article upon 

 the subject, in the foregoing pages, be- 

 sides accurately explaining the mechan- 



