518 SAMUEL PIERPONT LANGLEY. 



ardization of time in the United States and in other countries, and 

 through its financial returns the instrumental equipment of Alle- 

 gheny Observatory ^vas rendered possible, and likewise the great 

 discoveries in astrophysics by its dii-ector. 



At the age of 35, in ISOl), Mr. Langley published his first two 

 papers, the ver}' first being a report of two pages on the observation of 

 the total eclipse of August 7, 1869, at Oakland, Ky., and the second, 

 " a proposal * * * for regulating from this observatorj^ the 

 clocks of the Pennsylvania Central and other railroads associated 

 with it." 



When we recall the intolerable inconvenience Avhich attached to the 

 changing of time in every 40 or 50 miles of travel, and the empirical 

 method by wdiich clocks and watches were set, resulting in annoyance, 

 confusion, delay, and disaj)p()intment, these early labors of Mr. Lang- 

 ley, resulting in our standard time system and in the almost universal 

 regulation of public clocks through electrical signals from observa- 

 tories, must be counted, if not an important advance in knowledge, a 

 really great contribution to the convenience, comfort, and Avelfare of 

 mankind. 



While these practical efforts to secure a fund for the equipment of 

 the observatory Avere maturing, Mr. Langley had the opportunity of 

 carrying on astronomical work under other auspices. In 1869 he 

 took charge of a coast survey party to observe the total eclipse of 

 August 7 of that year at Oakland, Ky., resulting in the brief paper 

 above referred to, and in 1870 he accompanied a Government eclipse 

 expedition to Jerez de la Frontera, which was under the general direc- 

 tion of Prof. Joseph Winlock, and included on its staff besides Mr. 

 Langley, Professors Young and Pickering, both of whom have since 

 become among the foremost of American astronomers. 



He had meanwhile not lost his interest in the time service, the meth- 

 ods of which he described in an article in the American Journal of 

 Science in 1873, proposing, in addition to transmitting time to rail- 

 roads, to suppl}^ it to watchmakers and jewelers and to cities in 

 general for their public clocks. 



Almost from the beginning of his astronomical work he had 

 devoted his attention to the sun, his investigations being chiefly 

 astrophysical in character, and among his earlier observations in 

 this field were his sun-spot studies, carried on about 1873. From 

 that time on until 1880 he was engaged in minute telescopic study 

 and drawing the details of the surface of the sun, and especially of 

 sun spots. Photography had not begun to be used for such pur- 

 poses, and his skill and accuracy in making drawings of observations 

 of these phenomena were particularly valuable. Indeed, it is de- 

 clared by astrophysicists that his sun-sjDot drawings made at Alle- 

 gheny i^rior to 1875 are even yet to be regarded as the best recorded 



