LITERARY NOTICES. 



6^? 



tion in schools, and with improvement in 

 methods and results there comes a demand 

 for the special cultivation of teachers, by 

 means of institutes and normal schools. 



This complex machinery of education 

 must be thoroughly understood by every 

 efficient teacher in its principles and practi- 

 cal working, and Prof. Phelps's book has 

 been prepared to facilitate this special pro- 

 fessional culture. It is written with the 

 warmth of a man who is in earnest, and 

 with the clearness of one who understands 

 his subject. Unsettled questions and diffi- 

 culties in education are recognized, with ju- 

 dicious suggestions, as in the following pas- 



"The question as to what shall be taught in 

 our common schf^ols is yet to receive a definite 

 solution. Next in importance to right methods 

 of teaching ranks the subject-matter of teach- 

 ing. 'What knowledge is of most worth? What 

 branches are the most useful, first for disci- 

 pline, and second for use or particular applica- 

 tion ? ' Upon this subject we have no settled 

 policy. As a consequence, many things inferior 

 usurp the place of those of superior worth. The 

 dry details of so-called geography, the abstract 

 definitions, rules, and formulas of grammar, 

 the comparatively valueless signs and symbols 

 of algebraic notation, consume a vast amount 

 of the time that should be devoted to the study 

 of the earth, its climate and productions in their 

 relations to man, and the course of human his- 

 tory; of the English language, as a means of 

 communication, and of the living sciences which 

 lie at the basis of all the arts and industries of 

 life. But it is futile to attempt a revolution in 

 subject-matters while teachers, their attain- 

 ments, and methods of work, are so inadequate 

 to the public needs. It is idle to talk of the ne- 

 cessity of the elements of physics and chemis- 

 try, botany and physiology, natural history and 

 agriculture, so long as we have neither the 

 knowledge nor the skill requisite to their proper 

 treatment. Of what value would these sciences 

 be to the people When mechanically memorized 

 from the printed page, as are most of the sub- 

 jects now in our common-school curriculum ? 

 To be of use, either for discipline or applica- 

 tion, they must be properly taught by observa- 

 tion, experiment, aud demonstration. In short, 

 their objects must be seen, handled, analyzed, 

 compared, and classified. These practical sci- 

 ences must be investigated by methods and pro- 

 cesses analogous to those by which they have 

 been themselves developed, and thus far per- 

 fected. Can our children be expected to grope 

 their way to these natural processes in spite of 

 their teachers ? or, must the latter first be made 

 capable of leading the way, inspiring the young 

 by the fullness of their learning, and the skill of 

 their methods ? Until our children and youth 

 learn the right use of their own powers, it is iu 



vain to expect that they can master the powers 

 of Nature, or accomplish any other important 

 result." 



The Uranian and Neptunian Systems, in- 

 vestigated WITH the 26-inch Equato- 

 rial OF the United States Natal 

 Observatory. By Simon Newcomb, 

 LL. D., Professor United States Navy. 

 Washington Observations for 1873. Ap- 

 pendix I. Government Piinting-Office, 

 1875, pp. 72, 4to. 



This pamphlet, separately printed, con- 

 tains the first published discussion of work 

 done by the 26-inch Clark refractor of the 

 Naval Observatory. What this work was, 

 and how great necessity existed for its pros- 

 ecution, may be gathered from the first two 

 paragraphs of the memoir : 



" The remoteness of the two outer planets 

 of our system renders the accurate investiga- 

 tion of their satellites a task of great difficulty. 

 This is strongly evinced by the great discord- 

 ances between the conclusions respecting the 

 masses of those planets which have been reached 

 by various observers. Thus, in the case of 

 Uranus, Von Asten, the latest investigator, cites 

 a number of determinations of the mass from 

 recent observations, which range between tj'^j. 

 and lyjTs [of the sun's mass], so that the largest 

 result is nearly half as large again as the small- 

 est. Even difi'erent results, obtained by the 

 same observer nnder slightly different circum- 

 stances, were surprisingly discordant. The best 

 determination was that of Struve ; but even 

 here there was a difl"erence of four per cent, be- 

 tween the results from the two [brighter] sat- 

 ellites. In the case of Neptune, discordances 

 of the same kind showed themselves ; Struve's 

 mass being greater than that of Bond by one- 

 third. 



" For these and other reasons, when the 26- 

 inch equatorial, with an object-glass nearly per- 

 fect in figure, was mounted at the Naval Obser- 

 vatory, the observation of the satellites of the 

 outer planets, with a view of determining not 

 only the elements of their orbits, but more es- 

 pecially the masses of the planets, was made 

 the first great work of the instrument. Enter- 

 taining the opinion that, in the present state of 

 astronomy, it was better to do one thing well 

 than many things inditferently, the minor ar- 

 rangements of the instrument were all made sub- 

 servient to the end in view, and no other serious 

 work of a dissimilar character was attempted 

 during the continuance of the observations." 



It is well known that the two brighter 

 satellites of Uranus, viz., Oberon and Ti- 

 tania, are quite faint objects even in the 

 large 15-inch telescopes of Harvard College 

 and of Pulkova, but the two interior satel- 

 lites, Ariel and Umbriel, are incompara- 



