508 STEPHEN ALEXANDER. 



completed the observatory, which the generosity of his friend and 

 admirer, General Ilalsted, had provided; and after weary years of 

 waiting there came at last before his death the great instrument he 

 had dreamed of. It was my privilege to point it for him upon some 

 of those wonderful objects he had so long desired to see with his own 

 eyes, and to listen to his expressions of satisfaction and delight. But 

 the great telescope came too late for him to use it much ; he labored, 

 and others entered into his labors. 



As was the case with all college professors thirty years ago, his time 

 and strength were so occupied by the duties of instruction and dis- 

 cipline, in the class-room and the faculty meeting, that little remained 

 for other work. Still he accomplished a good deal in the way of 

 writing, as well as in observing. Though he could not be called a 

 prolific author, yet he published in various scientific periodicals a 

 very considerable number of papers, some of which were very elabo- 

 rate, and excited no little interest and discussion. Probably the most 

 important and characteristic of them were the four following : a paper 

 upon "The Physical Phenomena attendant upon Solar Eclipses"; one 

 on " The Fundamental Principles of Mathematics " ; one on " The 

 Origin of the Forms and the present Condition of tiie Clusters of 

 Stars and several of the Nebula?"; and finally, his treatise on " Certain 

 Harmonies in the Solar System." The first of these was read at tlie 

 centennial meeting of the American Philosophical Society in 1843, 

 and a full abstract, evidently revised and corrected by the author, 

 appears in the volume of Proceedings then published. It shows a 

 most extensive range of reading, and is an exceedingly thorough, 

 orderly, and exhaustive, though hardly discriminating, summary of 

 everything that any observer ever really saw, or thouglit he saw, on 

 such occasions. The pajier on the Fundamental Principles of Mathe- 

 matics was first read before the American Academy in 1848, and 

 afterwards published in Silliman's Journal. It is an interesting, sug- 

 gestive, and eloquent essay. The subject permitted the author to indulge 

 his genuine Scotch love for metaphysics and hair-splitting, and he found 

 in it also opportunity for imagination and poetry to an extent that 

 makes the article curiously singular among mathematical disquisitions. 

 His discussion of Nebulai and Clusters of Stars appeared in Gould's 

 Astronomical Journal, in a series of papers running through many 

 numl)er3. The main purpose appears to be to show that many of the 

 nebuUe and star-clusters are stars, not in tlie process of formation, 

 but of disintegration, — that the nebular stage follows, in some cases, 

 instead of preceding, the stellar. 



