38 



KNOWLEDGE .K: SCIENTIFIC NEWS. 



[Mar., IC04. 



lighted room, and the observation of an illuminated ball 

 surrounded by the blackness of night, seen through the 

 mirage of its own atmosphere by means of a telescope. 

 Those who draw conclusions from observations should be 

 very careful in their reasoning, bearing in mind that 

 induction, while a powerful instrument in the construc- 

 tion of theories, is absolutely useless in their proof or 

 disproof. A theory of physical phenomena can be dis- 

 proved only by showing that it leads by deductive 

 reasoning to necessary conclusions that are inconsistent 

 with observed facts. ;\Ir. jMaunder's theory may explain 

 sufficiently well the lines on the copies of his drawings, 

 but it no more suffices to disprove the objective reality 

 of the canals observed on Mars than it does to prove 

 that there are only fi\-e canals, as seen by his boys. 

 The fact that an effect may be due to one cause, while it 

 may certainly also be due to another, affords no pre- 

 sumption that it is due to the first rather than to 

 the second, especially when the one explanation is 

 based upon artificial experiments and the other is 

 natural. 



Mr. Maunder's argument assumes that the canals are 

 seen as very faint lines, so faint that their existence is 

 doubtful even to experienced observers ; this may be true 

 when they are observed through any but an exceptional 

 atmosphere — and the atmosphere of Flagstaff is one of 

 the exceptions. There, even under ordinary conditions, 

 at the proper Martian season most of them are so easily 

 and certainly seen that there is no reasonable doubt about 

 them. Before Mr. Maunder ever disco\ered the psychical 

 effect, Mr. Lowell was perfectly aware of it himself, and 

 had studied it experimentally, which experiments he has 

 continued to the present time, with the result that he 

 finds a clear line of demarcation between confusion of 

 real and imaginary up to a certain degree of definite- 

 ness of the real, and an instant consciousness of the dif- 

 ference between the two above that limit. The brain is 

 not only conscious of the image, but directly conscious 

 of reality as opposed to illusion. If Mr. Maunder's 

 drawings had contained some canals for comparison 

 with the imaginary lines, this difterence would probably 

 have been apparent. 



The beha\iour of the canals, their waxing and waning 

 with the advance of the Martian seasons, is proof positive 

 that they are not due to the integration by eye of perma- 

 nent faint markings, and it is more difficult to account for 

 the gradual and regular advance and retreat of such 

 markings along the line of a canal than for the growth 

 and decadence of the canal itself. Mr. Maunder's ex- 

 planation seems to substitute an uncertain and almost 

 impossible phenomenon for a very certain and probable 

 one._ From 8,500 determinations of the canals, Mr. 

 Lowell has recently shown that they come into sight 

 after the melting of the polar cap in times that are 

 directly proportional to their distances from that cap 

 measured in latitude. The enormous improbability of 

 any such agreement in 375 drawings, the number he 

 used, is so great as to run into the millions to one. 



The logical conclusion of Mr. Maunder's argument, if 

 valid, is that no faith is to be put in the reality of things 

 seen, if anybody has e\ er been deceived in the appearance 

 of such things. The scientific \-alue of facts would then 

 be liable to complete emasculation by the ignorance 

 carelessness, or male\olence of an observer. It is time 

 an end should be put to the inquisitorial fashion of re- 

 fusing credence to scientific discoveries until they shall 

 have received the official recognition of the self-constituted 

 authorities, especially when those authorities do not 

 represent experts in the subject in (juestion. That it is 

 useless to continue the observation of planetary detail, 



because henceforth no reliance can be placed on what 

 observers may tell us they have seen of such, can only be 

 the doctrine of what may be called an " impressionist " 

 school of science. If Mr. Maunder claims that his ex- 

 planation is simply one mode of accounting for the 

 appearance of the canals, he is practically throwing 

 doubt upon their existence without taking the responsi- 

 bility for it. 



In the course of the discussion of Mr. ]\Iaunder's com- 

 munication, Professor Newcomb said : " We all know 

 how one improves by practice, and I think there is such 

 a thing as improvement of the art of seeing things dif- 

 ferent from what they really are." This is a gratuitous 

 slur upon scientific obser\ation, to be justified only by 

 the heat of a violent quarrel, and inexplicable under the 

 present circumstances. Surely, Professor Newcomb 

 cannot believe that the statements of an observer are 

 any the less credible because he has had experience ? 

 No ; these experiments show conclusively that observers 

 must be trained to their work, that even descriptions of 

 phenomena are of little value unless made by those who 

 are experienced in observing phenomena of the kind de- 

 scribed. The reports of such observers must be accepted 

 as truly indicative of fact until they shall have been 

 proved to be false, which can be done only by direct 

 appeal to observation. Williaii Edward Story. 



Worcester, Mass., U.S.A., January 2, 1904. 

 [Mr. Story criticises the paper communicated by Mr. Evans and 

 myself to the R AS. without first having done us the honour 

 of reading it. This method has some disadvantages; one being 

 that many of Mr, Story's remarlis have no bearing at all on the 

 questions with which we actually dealt. Want of space pre- 

 vents my dealing with the details of Mr. Story's paper in the 

 present number of "Knowledge," but if the subject suffi- 

 ciently interests its readers I may return to it on a later occasion. 

 For the present, it is sufficient to enter a strong protest against 

 Mr. Story's quite uncalled-for attack upon Professor Newcomb. 

 — E. Walter Malnder.] 



The Obelisk of Mo\ii\t 

 Pelee. 



Wb. reproduce herewith a remarkable photograph taken 

 by Mr. E. O. Hovey, for which we are indebted to our 

 contemporary, the Scientific American. It represents one 

 of the most peculiar and interesting phenomena of the 

 recent eruptions of Mount Pelee. This was the growth 

 of the tooth-like column of rock which arose out of the 

 centre of the crater. It was first observed (by Professor 

 Lacroix) in October, 1902, amid the dense smoke and 

 steam overhanging the mountain. It was then estimated 

 to be about 295 feet above the rim of the old crater. Put 

 subsequent observations proved it to be steadily growing, 

 and after some months had attained a height of over 

 1000 feet. Professor Heilprin noted a growth of about 

 20 feet in four days. 



\'arious explosions and movements of the earth altered 

 the relative height of the obelisk. It rose and fell and 

 large portions became detached. Bit by bit it then 

 receded again, sinking as much as 150 feet during one 

 night, but frequently rising again temporarily. This 

 continued during many months, till finally it disappeared 

 within the cone. 



The cause of this curious apparition can but be vaguely 

 surmised. It has been suggested that the vent of the 

 volcano in olden days had become filled with solidified 

 lava, and when the first outbreak occurred this whole 

 mass was raised bodily up, as a cork is forced upward 

 from a bottle. 



