EDITOR'S TABLE. 



491 



Prof. Henry's investigations, constitut- 

 ing an advance of scientific knowl- 

 edge in tliis brancli of acoustics, that 

 Prof. Tyndall has omitted or " sup- 

 pressed " in liis work? If any tiling 

 has been accomplished in this country 

 toward the scientific solution of such 

 acoustical problems in relation to fog- 

 signaling if any new light has been 

 cast upon the phenomena that ex- 

 plains anomalies and reconciles contra- 

 dictions, which was not acknowledged 

 by Prof. Tyndall in his book we sub- 

 mit that it was the obvious duty of the 

 writer in the Nation to point out what 

 it was. He should have indicated the 

 gap in Prof. Tyndall's summary of the 

 present state of knowledge, or he should 

 have shown us what principles or re- 

 sults, there stated, are due to American 

 research. He says: " It is no part of 

 our present purpose to institute a critical j 

 inquiry into the conflicting views of 

 Prof. Henry and of Prof. Tyndall with 

 regard to the hypotheses respectively 

 espoused by each for the explanation 

 of the phenomena of sound, in its pas- 

 sage through wide tracts of air." Yet 

 the whole question turns on the scien- 

 tific " views " contributed by Prof. 

 Henry which it is alleged that Tyndall 

 has ignored. He speaks of the views 

 "respectively espoused" by the par- 

 ties; but the question is on the views 

 originated. Prof. Henry is understood 

 to adopt the theory propounded by 

 Prof. Stokes at the British Associa- 

 tion in 1857, according to which sound- 

 waves are tilted through the air under 

 the influence of wind. That theory is 

 certainly not " suppressed " from the 

 new edition of " Sound." In his re- 

 joinder to Prof. Tyndall's letter, the 

 Nation's critic reaflirms his assertion, 

 saying, "The question between us is 

 not one of science^ but of historical 

 facty But his complaint in the first 

 article was certainly of the non-recog- 

 nition of " American science." Obvi- 

 ously Prof. Tyndall had to decide what 

 is science and what is not, which looks 



to us very much like a scientiflc ques- 

 tion. In his "summary of existing 

 knowledge," it was not his* business 

 merely to chronicle experiments. He 

 had to deal only with such systematic 

 inquiries into causes as yield results 

 properly entitled to take their place 

 in the body of scientific knowledge. 

 We do not say that Prof. Henry's re- 

 searches have failed to extend the do- 

 main of positive scientific knowledge, 

 but only that the writer in the Nation 

 was bound to establish this, before ac- 

 cusing Prof. Tyndall of delinquency in 

 not recognizing it. 



But it is the closing passage of the 

 Nation's article which has excited the 

 greatest surprise, betraying, as it obvi- 

 ously does, a vicious state of feeling on 

 the part of the writer. He there rep- 

 resents Prof. Tyndall as having claimed 

 to demolish the authority of Prof. Hen- 

 ry, and as swaggering over the " ruin " 

 he had accomplished. In half a dozen 

 hues, Tyndall is accused of "super- 

 ciliousness," "self-complacency," "van- 

 ity," "conceit," "arrogance," and "self- 

 laudation ; " and this upon an utter- 

 ly false and absurd interpretation of 

 some incidental remarks in his preface. 

 The following is the passage that called 

 forth this storm of ofl'ensive epithets: 



"The clew to all the difficulties and 

 anomalies of this question is to be found in 

 the aerial echoes, the significance of which 

 has been overlooked by General Duane, and 

 misinterpreted by Prof. Henry. And here 

 a word might be said with regard to the in- 

 jurious influence still exercised by authority 

 in science. The affirmations of the highest 

 authorities, that from clear air no sensible 

 echo ever comes, were so distinct, that my 

 'mind for a tim^ refused to entertain the idea. 

 On the day our observations at the South 

 Foreland began, I heard the echoes. They 

 perplexed me. I heard them again and 

 again, and listened to the explanations of- 

 fered by some ingenious persons attlie Fore- 

 land. They were an ' ocean-echo ; ' this is 

 the very phraseology now used by Prof. 

 Henry. They were echoes ' from the crests 

 and slopes of the waves ; ' these are the words 

 of the hypothesis which he now espouses. 

 Through a portion of the month of May, 



