Februasy 20, 19.14] 



SCIENCE 



275 



matics, then, as now the best training for a 

 scientist, and he never forgot them. Neither 

 did he slight the modem languages nor the 

 vernacular, for nothing but the best of Eng- 

 lish ever proceeded from his mouth or pen. 



Graduating at Harvard in 1876, he had 

 already shown a marked talent for both 

 mathematics and physics, and, receiving a 

 traveling fellowship, he proceeded for further 

 study to Leipzig, where "he worked in Wiede- 

 mann's laboratory, and obtained the degree 

 of Ph.D. in 1879. After this he spent another 

 year at Berlin with Helmholtz, from whom he 

 drew much inspiration. During these four 

 years he had not only obtained skill in experi- 

 mental research, but he had obtained a thor- 

 ough grounding in the principles of mathe- 

 matical physics, then almost entirely un- 

 taught in any American university. 



Returning to the United States in 1880, 

 Peirce spent a year in teaching at the Boston 

 Latin school, and in 1881 received the appoint- 

 ment of instructor in mathematics at Harvard. 

 This was not what he desired most, but he 

 took hold of the work with enthusiasm, and 

 among other subjects taught the calculus in 

 a two-years' course, alternating with Professor 

 Byerly. A splendid course it was, and those 

 students who took it under one disputed with 

 those taking it under the other as to which 

 was the better teacher. But the most notable 

 course instituted by Peirce and shared by this 

 pair of masterly teachers was that one in 

 which Peirce treated the theory of the New- 

 tonian potential function, and Byerly the 

 theory of Fourier's series. The writer well 

 remembers his feeling of mystification, when 

 at the end of his freshman year, on consulting 

 the elective pamphlet to select courses for the 

 next year, he came across the announcement. 

 Arbitrary Functions and the Theory of the 

 Potential. What on earth were arbitrary 

 functions, and what was the " potential " ? 

 His highly respected teacher in the high 

 school, hitherto an unfailing adviser, could 

 not tell. But as a matter of fact this course 

 marked a new era in American university 

 work, for, as has been stated above, the teach- 

 ing of mathematical physics in this country 



was practically non-existent. I say this 

 advisedly, having in mind that mechanics was 

 taught to a certain extent, and that there 

 were one or two courses on the theory of light, 

 but the character of the teaching was totally 

 different from that of the present era. Peirce 

 had come back from Germany full of enthu- 

 siasm for the thoroughgoing German methods 

 and the magnificent achievements of Gauss, 

 Riemann and Dirichlet, which had opened up 

 to him a new world. The backbone of theo- 

 retical physics is the subject of partial differ- 

 ential equations, and the most suitable gate 

 to enter by is the theory of the potential 

 belonging to forces acting according to the 

 law of the inverse square. This Peirce had 

 the insight to perceive, and made it his part 

 to work up a course on this subject, which he 

 treated with rare clearness and skill. The sub- 

 ject-matter of this course afterwards appeared 

 in his treatise " Elements of the Theory of 

 the Newtonian Potential Function," which 

 passed through three or four editions and 

 constituted a model of what such a work 

 should be. One other of the fruits of his 

 teaching was the short table of integrals, 

 whose convenience has brought him the grati- 

 tude of many a student of the calculus. 



In 1884 came the appointment as assistant 

 professor of mathematics and physics, and 

 Peirce took his place in the department of 

 physics, to which he rightly belonged, and in 

 which he was able to do his share in the recon- 

 stitution and modernization of that depart- 

 ment which it was now to undergo in the new 

 Jefferson laboratory. This was at the begin- 

 ning of systematic laboratory work in physics 

 in this country, and there was a certain 

 amount of friction in getting the new ideas 

 started. In 1888 with the retirement of Pro- 

 fessor Joseph Levering he was succeeded by 

 Peirce in the Hollis professorship of mathe- 

 matics and natural philosophy, a decided 

 honor for so young a man. At the same time 

 Professor John Trowbridge became director 

 of the laboratory, and from this time on there 

 was a rapid development of the laboratory 

 work into what has become one of the best 

 organized courses in the country, while re- 



