1882.] ^J-^ [Chase. 



Thomas Young are quoted : — "It must be confessed that, ia this country, 

 the cultivation of the higher branches of the Mathematics, and fhe inven- 

 tion of new methods of calculation, cannot be too much recommended to 

 the generality of those who apply themselves to Natural Philosophy ; but 

 it is equally true, on the other hand, that the first mathematicians on the 

 Continent have exerted great ingenuity in involving the plainest truths ot 

 mechanics in the intricacies of Algebraical formulas, and in some instances 

 have even lost sight of the real state of an investigation, by attending 

 only to the symbols, which they have employed for expressing its steps." 

 After this quotation Leslie proceeds as follows : — "Laplace's intricate 

 formula has been since unraveled by the acute discrimination of Mr. 

 Ivory, who disjoined it into two separate portions ; the one depending on 

 the adhesion of the watery film to the inside of the tube, and the other 

 resulting from half the cohesion of the particles of the liquid to each other. 

 But our ingenious countryman deduced these elements of the complete 

 force from the simplest physical principles, availing himself of the property 

 of equable tliffusion of pressure through the mass of a fluid. The same 

 investigation gave the measure and limits of depression observed in mer- 

 cury and some other liquids." 



259. Cooperative MetJwds. 



Since the invention of Hamilton's quaternions and Peirce's linear asso- 

 ciative algebras, the temptation for mathematicians to involve "the plain- 

 est truths of mechanics in the intricacies of algebraical formulas" has 

 greatly increased. The higher the algebra, the smaller is the number 

 who are able to understand it. While it may be no part of an investiga- 

 tor's duty to "popularize" science, no result can be rightly regarded as 

 belonging to the ■dominion of science until it has been so far popularized 

 as to be brought within the grasp of the majority of scientific men who 

 are willing to follow the several steps of the original investigation. Labor 

 which is expended on intricate solutions of problems which can be simply 

 deduced from "the property of equable diflusion of pressure through the 

 mass of a fluid," or from other properties of elastic media, is either labor 

 wholly wasted, or, at best," an exercise of ingenuity which serves as a 

 harmless recreation. On the other hand, the use of well-known physical 

 relations as clews for the discovery of coordinate relations, alternating 

 with analytical solutions of problems which are suggested bj'' such dis- 

 coveries, combines the advantages of theory and observation in ways 

 which are most helpful to scientific progress. Whenever any given result 

 may be reached by two or more difierent methods, the shortest and sim- 

 plest is always most commendable. 



200. Lunar Magnetic Polarization. 



The relations between magnetic fluctuations and gravitating tendencies to 

 the restoration of equilibrium in disturbed atmospheric or fethereal currents 



