April 24, 1896.] 



SCIENCE. 



631 



quate and inconvenient, but the space available 

 in the museum has become much too restricted, 

 while both offices and museum, with all their 

 valuable accumulations, are subject to danger 

 of loss by Are. The advantage to Canada of 

 having an adequate display of the mineral 

 wealth of the country can scarcely be exagger- 

 ated, and that the museum, even in its present 

 state, possesses much interest to the general 

 public, is evidenced by the fact that more than 

 26,000 visitors have been registered during the 

 year. 



UNIVERSITY AND EDUCATIONAL NEWS. 



Yale University receives $200,000 through 

 the marriage of Mrs. T. C. Sloane. Mr. Sloane 

 had left part of his estate as a trust fund, the 

 above amount to go to Yale University in case 

 of Mrs. Sloane's second marriage. 



The will of the late Ephraim Howe leaves 

 $40,000 to Tufts college for a new building to 

 be known as the Howe memorial. 



The New York Evening Post states that the 

 library of Cornell University has secured, by 

 purchase, through the Sage endowment fund, 

 the extensive collection of works on South 

 America gathered, mainly during an eight 

 years' residence in Brazil, by Herbert H. Smith, 

 of the Brazilian Geological Commission. 



It is understood that Edinburgh University 

 will receive £20,000 from the estate of the Earl 

 of Moray as an endowment fund for the pro- 

 motion of original research in the University. 



The Senate of the Glasgow University, has 

 conferred the degree of D. D. on Prof. Thisel- 

 ton-Dyer and on Prof. Andrew Gray. 



The St. Petersburg Medical Academy has re- 

 ceived from the Russian government $2,500 for 

 experiments with the X-rays. 



DISCUSSION AND COBBESPONDENCE. 

 CERTITUDES AND ILLUSIONS. 



Editor of Science : I am very much afraid 

 that physicists will find themselves utterly un- 

 able to follow, or, at least, to understand. Major 

 Powell in his philosophical dissertations on the 

 fundamental concepts of mechanics, and that 



they will be compelled to conclude that his 

 philosophy is not ' Natural ' Philosophy, in the 

 generally accepted sense. 



Believing this to be inevitable, it is hardly 

 worth while to continue at any length a discus- 

 sion or critical examination of the very inter- 

 esting propositions which he has laid down. It 

 may be of use, however, to invite his attention 

 to the fact that in the answers to my questions 

 relating to ' Rest and Motion,' which he gave 

 in this Journal for April 17th, he continues to 

 ignore entirely the only serioUs issue raised by 

 them. It can hardly be supposed that Major 

 Powell is undertaking to establish a concept of 

 motion independent of relativity, yet he seems 

 to overlook the necessity of giving it considera- 

 tion. When, in answer to my question, he de- 

 fines motion as ' change of position ' it only 

 leaves the question where it was before, if not 

 in even greater obscurity. ' Position ' implies 

 a relation ; then motion implies a relation and 

 cannot be predicated of any one of Major 

 Powell's several orders of units. 



His statement that "the speed of a particle 

 is constant in reference to itself at different 

 times ' ' is meaningless, if the commonly ac- 

 cepted idea of motion is correct. If it is not 

 correct, and that of Major Powell is, then — the 

 bottom has dropjjed out. 



As to his suggested correction of a typograph- 

 ical error in his previous statement relating to 

 the velocity of light, if molar be substituted for 

 molecular in that statement, it remains quite as 

 astounding as before. I mention this only that 

 he may note that apparently he has uot de- 

 tected the real absurdity involved. M. 



April 19, 1896. 



is there more than one kind of knowl- 

 EDGE ? 



' ' My praise shall be dedicated to the mind it- 

 self. The mind is the man, and the knowledge oj 

 the mind. A man is but tvhat he knoweth. The 

 mind itself is but an accident to knowledge, for 

 knowledge is a double of that which is. The truth 

 of being and the truth of knowing is all one.'" — 

 Praise of knowledge. 



I am pleased to find in the current number of 

 Science (April 3, 1896), that after seven months 



