PUNISHING A SENIOR WRANGLER. 145 



he aware of the meaning of his words? Will he deny that, from first 

 to last, during the interval of condensation, heat is being generated ? 

 Will he deny to the air the power of radiating such heat ? He will 

 not venture to do so. Take, then, the interval of condensation as one- 

 thousandth of a second. I ask him to inform those whom he professes 

 to instruct, what is the probable number of heat-waves which have 

 escaped in this interval. Must they not be numbered by thousands of 

 millions ? In fact, by his " merely momentary," he actually assumes 

 that what is momentary in relation to our time-measures is momentary 

 in relation to the escape of ethereal undulations ! 



Let me now proceed more systematically, and examine his rejoin- 

 der point by point. It sets out thus : 



" In the notice of Mr. Spencer's works that appeared in the last number of 

 this Review, we had occasion to point out that he held mistaken notions of the most 

 fundamental generalizations of dynamics; that he had shown an ignorance of 

 the nature of proof in his treatment of the Newtonian Law; that he had used 

 phrases such as the Persistence of Force in various and inconsistent significa- 

 tions; and more especially that he had put forth proofs logically faulty in his 

 endeavor to demonstrate certain physical propositions by a priori methods, and 

 to show that such proofs must exist. To this article Mr. Spencer has replied in 

 the December number of the Fortnightly Review. His reply leaves every one 

 of the above positions unassailed." 



In my " Replies to Criticisms," which, as it was, trespassed unduly 

 on the pages of the Fortnightly Review, I singled out, from his allega- 

 tions which touched me personally, one that might be briefly dealt 

 wdth as an example ; and I stated that, passing over other personal 

 questions, as not interesting to the general reader, I should devote the 

 small space available to an impersonal one. Notwithstanding this, 

 the reviewer, in the foregoing paragraph, enumerates his chief posi- 

 tions ; asserts that I have not assailed any of them (which is untrue) ; 

 and then leads his readers to the belief that I have not assailed them 

 because they are unassailable. 



Leaving this misbelief to be dealt with presently, I continue my 

 comments on his rejoinder. After referring to the passage I have 

 quoted from Prof. Tait's statement about physical axioms, and after 

 indicating the nature of my criticism, the reviewer says : 



" Had Mr. Spencer, however, read the sentence that follows it, we doubt 

 whether we should liave heard aught of this quotation. It is: 'Without further 

 remark we shall give Newton's Three Laws ; it being remembered that, as the 

 properties of matter might have been such as to render a totally different set 

 of laws axiomatic, these laws must 'be considered as resting on convictions drawn 

 from observation and experiment, and not on intuitive perception.'' This not only 

 shows that the term ' axiomatic ' is used in the previous sentence in a sense that 

 does not exclude an inductive origin, but it leaves us indebted to Mr. Spencer 

 for the discovery of the clearest and most authoritative expression of disap^ 

 proval of his views respecting the nature of the Laws of Motion." 



VOL. V. — 10 



