as I know, to the derivation of English words and affixes. His textbooks on that subject are full of ingenious observation and careful scientific deduction. He was also a great reader of old English books in their early editions, and he treasured in his memory the curiosities of spelling and pronunciation, the rhymes and puns and the like which he found there. He busied himself also with the Pennsylvania Dutch, as it is called, and traced it to its sources in Europe. He read largely the German works on the science of language, but he was an independent observer, and more likely to be biased by his critical temper than by absorption in any systems."
Professor Haldeman was actively interested in education, and occupied professorial chairs during a large part of his life. He was chosen Professor of Zoölogy in the Franklin Institute in 1842, and afterward filled the positions of chemist and geologist to the Pennsylvania State Agricultural Society in 1852; Professor of Natural History in the University of Pennsylvania, 1850 to 1853; professor in the chair of the same name in Delaware College, Newark, 1855 to 1858; and Professor of Comparative Philology in the University of Pennsylvania from 1869 till his death. He regularly attended the meetings of the Pennsylvania State Teachers' Association. Professor Haldeman had in great part been induced to change his studies from zoölogy mainly to linguistics by the failing condition of his eye-sight; in a similar manner an order to take exercise for his health became the occasion of his engaging in the study of archaeology in 1875. He proceeded to carry out an intention he had long entertained of digging for aboriginal relics in the Chickies Rock retreat, a shallow cave on his own property. Here he obtained the interesting collection which he presented to the American Philosophical Society, and which he described in a monograph "On the Contents of a Rock Retreat in Southeastern Pennsylvania," published by the society since his death, with fifteen large quarto plates. He also published archæological papers in the "Smithsonian Report" for 1877, in the "American Antiquarian" and "American Naturalist," and through the American Association.
He was a prolific and successful writer on a curious variety of subjects, some of which appear incongruous with each other. The list of his scientific publications prepared by his daughter, Mrs. Eliza Figgelmery, includes ten titles in conchology, twenty-three in entomology, two on arachnidæ, five on Crustacea, six on annelides and worms, seven in geology and chemistry, thirty-three in philology, seven in archaeology, and twenty-nine miscellaneous publications. Outside of the immediate circle of subjects with which his name is most prominently associated, he published one or two works of literary criticism, an essay on the "Tours of a Chess-Knight," showing how the knight can pass over the whole chess-board, touching each square but once; a collection of "Rhymes of the Poets," by Felix Ago, containing specimens of false rhymes from one hundred and fourteen prominent writers;