ACADEMY OF SCIENCES.] BIOGRAPHY. 163 



which he commenced ordering from Europe, upon his personal responsibility, the instruments 

 required for the proposed work. 



Meanwhile there came into the science of astronomy a new method of research with which 

 Gould became early identified and with whose development he is closely associated. Lewis 

 Rutherfurd, of New York, a pioneer in photography, had applied that art to the heavens and, 

 overcoming very considerable difficulties by means of improved technique, he had obtained 

 excellent large-scale photographs of limited areas of the sky. Much impressed by these photo- 

 graphs, Gould volunteered, in February, 1866, to investigate their possible utility as a new 

 method of astronomical research. Rutherfurd had already designed and constructed apparatus 

 for measuring the positions of the star images on the plates, and upon Gould devolved the 

 task of investigating the new tools as well as the subject-matter to which they should apply, 

 and of pushing both tools and plates to the utmost limit of attainable precision. A preliminary 

 account of his first conclusions, based upon photographs of the Pleiades taken in March, 1866, 

 was presented to the National Academy of Sciences in August of the same year, but much 

 further labor was required before definitive results, from the photographs for the Praesepe 

 group as well as the Pleiades, could be realized. After long delay, intended to secure to Ruth- 

 erfurd the opportunity for prior publication, these final results were published by the academy 

 in 1888, as a part of its memoirs for 1870. Here, in Gould's supplement to Rutherfurd's work, 

 was shown for the first time that the photographic plate, when developed after exposure to the 

 stars, gives not merely a picture of the sky but an accurate reproduction of it adapted to measure- 

 ments of the highest precision. Mueller, one of the masters of modern astrophysics, character- 

 izes this work in the words "Durch diese Arbeiten, welche zum ersten Male an einem grosseren 

 Material die Anwendbarkeit der Photographie zu exacten Messungen am Himmel bewiesen, hat 

 sich Gould auch in der Geschichte der Astrophysik einen hervorragenden Ehrenplatz verdient." 



The scientific work accomplished by Gould in the 22 years following his first return from 

 Europe must be designated by any just critic as distinguished in character and remarkable 

 in amount. Consequent to this record, the year 1870 found him a man of middle age, established 

 position and repute, but with his major work not yet seriously entered upon. An index to his 

 outlook upon life at this period may be found in two notable addresses. In one of these, upon 

 the physical character and constitution of the sun, delivered as a series of lectures before the 

 Peabody Institute of Baltimore, he shows, as nowhere else, his interest in and familiarity with 

 the new phase of astronomical research then coming into vogue which we now call astrophysics. 

 That he did not actively engage in this new fine of research was due to no lack of sympathy or 

 appreciation of its promise. His address as retiring president of the American Association for 

 the Advancement of Science, delivered at the meeting of 1869, is largely devoted to an expo- 

 sition of his outlook upon the larger intellectual and spiritual interests of life. The "conflict 

 between religion and science" filled the air of that day with its clamor, and Gould improved 

 the opportunity offered by his position in American science to set forth earnestly and vigorously 

 his conception of the relations between the intellectual and the spiritual life. Upon questions 

 of this kind no man may pronounce definitive judgment, and the interest that still inheres in the 

 address is not to be sought from this side. It is, rather, an apologia pro vita sua, an expression 

 of the intellectual side of his own spiritual life. 



Five years had now elapsed since his first approach to the Argentine envoy with the 

 inquiries above noted. Sarmiento meanwhile had returned to his own land as its president and, 

 for the development of its educational system, he had inaugurated a policy of emphasizing the 

 natural sciences, with stress upon the element of research. Two years after this statesman 

 assumed his high office, at his invitation Gould sailed for the Argentine, via Europe, to execute 

 the projects that had been taking shape in his mind since 1865. Narrowly escaping entangle- 

 ment in the Franco-Prussian War of 1870, he arrived at Buenos Aires as the southern winter 

 was changing into spring and found his destination still far away. Proceeding by boat up the 

 La Plata to Rosario, and thence northwestward by a newly constructed railway across the pam- 

 pas, he found in Cordoba, the site chosen for his work, a mediaeval Spanish city of 30,000 



