easily the leader in the class-room. His high standing and popularity led to his being made a commissioned officer in the Institute Battalion at the beginning of our second year,military drill in those days was continued through two years of the course, and by the time class organization came "the office sought the man," and his quiet popularity compelled his service as president of the Class Association. He continued president of our Class Association, and foremost in all movements for kindling and continuing a strong fraternal spirit among its members, for eight years, until relieved in 1883 at his own very urgent request. Throughout our student days his high standards of thought and his hard common sense, voiced with rare tact, were potent forces that aided in establishing public opinion among the class on a rational and wholesome basis.

So soon as the course of instruction in laboratory work permitted the subject of his investigations to follow his natural choice, he developed a special interest in the phenomena of heat; and to the last this field of research was most attractive to him, and in it he did original work of a very high order of merit. His graduating thesis was on "The Atomic Theory as applied to Gases," and reported a study of the effect of temperature upon viscosity. This was a very noteworthy piece of scientific work, particularly so for an undergraduate, and was published, with abridgment of some parts and extension of others, in the Proceedings of the American Academy of Arts and Sciences in 1876, and attracted the favorable notice of physicists abroad.

In the vacation at the end of the third year he joined with his classmates Henck and the lamented Hollingsworth for a tramp in the White Mountains. Struck by the crudeness and the inaccuracy of the best maps of this region

then obtainable, Mr. Henck extemporized a rude planetable, and set to work at each summit visited to lay down the azimuth of all mountains and noteworthy topographical features visible therefrom. Holman seconded Henck's efforts ably in this work; while Henck became more and more interested in the matter, gave the remainder of his vacation to prosecuting the work, soon interesting Professor E. C. Pickering and others in a way that subsequently led directly to the formation of the Appalachian Mountain. Club, in which Holman took an active interest, although prevented by his lameness from joining many of the excursions. Among his published contributions to the work of the club, we find in the first volume of Appalachia, in 1876, "Notes on Two New Forms of Mountain Barometer," and in its third volume, in 1882, "Notes of Hypsometric Measurements of Some Points about Williamstown."

I have always understood that the lameness from which our friend suffered so severely for years first developed as the result of an overstraining of muscles while tramping and mountain climbing on this trip; but Henck holds that the first serious trouble began with an over-exertion in seeing the Centennial Exhibition in Philadelphia in the following year, when Holman was an enthusiastic member of our Technology Encampment on the Campus of the University of Pennsylvania. Holman himself seldom or never said. anything about the cause or the extent of his lameness, but for nearly twenty-five years manfully struggled to keep it in the background.

In the autumn of 1876, with the opening of the term following his graduation, he received the appointment of Assistant in Physics in the laboratories of the Institute; but his lameness, although still mainly confined to one knee, had greatly increased, and prevented him from entering

upon the duties of the position. In January, 1877, he wrote me regretfully of this delay, and stated that it had then held him back six months from work which he longed to undertake. In February, 1877, still on crutches, he sailed for the Azore Islands, in the hope that the sea voyage and the change would bring up his general health, and so conquer his infirmity. After an absence of six months he returned much improved, although not entirely recovered, but by December, 1877, was able to take his place in the Physical Laboratory.

He continued giving instruction under the title of Assistant for four years, and then received appointment as Instructor, at the beginning of the term 1880-81. In the fall of 1881, which is a noteworthy date as marking the beginning of General Walker's administration as President, Mr. Holman was elected secretary of the Society of Arts, an office requiring a good deal of attention in securing proper subjects for presentation, and calling for considerable work in the preparation of its reports and proceedings for publication. He continued in this position for two years, resigning only in order to obtain time for the preparation of a course of Lowell Institute Lectures on Heat, given in connection with Professor Nichols.

He was earnest in the work of promoting a wider spirit of fraternity through the Alumni Association, was a member of its Executive Committee from 1878 to 1882, and its vice-president in 1882 and 1883. The foundation of the alumni fund was directly due to his initiative, and he was foremost in many good efforts for the success of the Association in its early days.

In the years 1880 to 1883 it was frequently my good fortune to visit Holman and his mother at their home, where it was always a pleasure to note the relations existing

between them. Deprived as he was of his father's companionship and counsel, his mother, a woman of remarkable force of character and charm of manner, came to be his associate in study and work to an unusual degree; and I have never seen a companionship between mother and son that approached the ideal so closely. While he was secretary of the Society of Arts, his mother attended its meetings and prepared many of the abstracts of its papers for publication, proud to share in her son's work and glad to save his strength. Her sudden death in December, 1883, came to him with a shock and a sadness all the deeper because of this uncommon devotion and unity of life.

On July 1, 1884, he married Miss Marie O. Glover, of Brooklyn, N. Y., a graduate of Vassar College and a graduate of the Institute class of 1881. Miss Glover had shown rare quality as a student and excellent skill in research, as certain of her essays published later bear witness. With her intellectual vigor there was no abatement of the sweet spirit of womanliness and domesticity, and this union appeared ideal. For a few brief months the merited happiness appeared to have settled over all his affairs; but this was cruelly broken on May 5, 1885, by her death after a very brief illness. How powerful and sacred the influence and inspiration of her singularly strong and gentle character continued with him to the end is known only to his most intimate friends. He has left a touching record of it in almost the latest words that his failing strength could pen.

Professor Holman's own personality was of the rarest, most inspiring character that I have known; and I have not the skill in words to portray it, or make its peculiar quality plain to one who has not known him personally long and well. Alertness with patience, gentleness with

courage, intellect with warm sympathy, hearty merriment with the keen conscience of a Puritan, skill and ingenuity in mathematics no less than in mechanics, and withal delightfully human,-it is by this personality that his friends. will always recall him rather than by his writings or his researches.

WORK AS A TEACHER

As already stated, Professor Holman's work as a teacher at the Institute began in December, 1877, under the title of "Assistant in the Physical Laboratory." He continued in active work in the laboratory until December, 1895, by which time the lameness, from which he had suffered severely much of the time for nearly twenty years, had so progressed that he could no longer even be carried to his desk, as had been the practice for some time before he gave up attendance in the class-room. He was first listed as Assistant Professor in the Catalogue of 1882-83, Associate Professor in 1885, Professor of Physics in 1893, and in 1897 Professor Emeritus. Meanwhile, for five winters. or more, he also gave various "Lowell Courses" to evening classes of teachers and others.

During all these years of his teaching I saw and heard much of Professor Holman and of his work from two quite different points of view,― from my own visits to him in his home and in his laboratory, and from the reports that came to me from many of his students, several of whom became employed upon the works with which I was connected, and with whom "how things were going at the Institute" was always an interesting topic. The uniformly earnest terms of admiration and affection with which all who had come under Professor Holman's teaching spoke of his approachableness, his patience, his encouragement toward thorough work and honest interpretation, and his