January 24, 1908] 



SCIENCE 



137 



December 15, 1834, at Hanover, where his 

 grandfather and father successively occu- 

 pied the chair of natural philosophy in 

 Dartmouth College during the period from 

 1810 to 1858. He entered college early 

 and graduated with distinction in 1853 as 

 bachelor of arts. During his student days 

 he assisted his father in astronomical ob- 

 servations and accompanied him in 1853 on 

 a trip to Europe to purchase instruments 

 for the Shattuck Observatory, then in 

 course of erection. For two years after 

 graduation he taiight the classics at Phil- 

 lips Academy, pursuing at the same time 

 theological studies at the Andover Semi- 

 nary. In 1857 he went to Hudson, Ohio, 

 as professor of mathematics and natural 

 philosophy at Western Reserve. During 

 several summer vacations he assisted in the 

 governmental survey of the great lakes. 

 Responding to the call of patriotism in 

 1862, he was for four months Captain of 

 Company B in the 85th Regiment of Ohio 

 Volunteers, which was largely recruited 

 from students. 



In 1866 he returned to Dartmouth as 

 professor of natural philosophy and as- 

 tronomy, thus continuing the family tra- 

 dition. 



The next few years were stirring times 

 in astrophysical research. The spectro- 

 ecope was just beginning to be applied in 

 the study of celestial objects, with results 

 of surprising interest. The eclipse of 1868 

 was made memorable by the discovery by 

 Lockyer and Janssen of the method of ob- 

 serving the solar prominences. In spite of 

 heavy duties as teacher. Young applied 

 himself assiduously to solar research. He 

 observed the eclipse of 1869 at Burlington, 

 Iowa, establishing the fact of the gaseous 

 nature and truly solar origin of the corona. 

 Employing what was for those days a very 

 powerful spectroscope, he quite accurately 

 located the position of the green corona 

 line, which was thereafter known as No. 



1,474 on Kirchhoff's map of the solar spec- 

 trum. It was not until the eclipse of 1898 

 that the position of the line was more cor- 

 rectly located, by Professor W. W. Camp- 

 bell observing in India, and was shown not 

 to be represented by a dark Fraunhofer 

 line. At the eclipse of 1869 Young also 

 looked for, but failed to detect, the reversal 

 of the dark lines at the moment of internal 

 tangency of moon and sun. But he real- 

 ized his expectations at the Spanish eclipse 

 of the next year, when he discovered the 

 "flash spectrum." He describes it in these 

 words: "The moment the sun is hidden, 

 through the whole length of the spectrum, 

 in the red, the green, the violet, the bright 

 lines flash o.ut by hundreds and thousands, 

 almost startlingly; as suddenly as stars 

 from a bursting rocket head, and as evan- 

 escent, for the whole thing is over within 

 two or three seconds. ' '- This phenomenon 

 was subsequently observed visually in a 

 more or less satisfactory way by different 

 astronomers at other eclipses, but it was 

 not photographically recorded until 1896, 

 when it was caught by Mr. W. Shaekleton 

 at Nova Zembla with the prismatic camera. 

 In the early seventies Professor Young 

 gave much attention to the spectrum of the 

 chromosphere and to the prominences. 

 Many of his delineations of these have be- 

 come classics from their reproduction in 

 various works and text-books. He devised 

 an improved form of solar spectroscope 

 which served his purpose very effectively. 

 His assiduity was rewarded by his observa- 

 tion of a number of rather unusual solar 

 phenomena : such as the highest recorded 

 prominences, extraordinary velocities indi- 

 cated by distorted lines, i;p to 320 miles 

 per second ; violent solar agitation associ- 

 ated with magnetic storms. He was the 

 first to attempt to photograph the promi- 

 nences and attained a partial success 

 (1870). With the wet plates then neces- 

 = The Sun, p. 82. 



