SAMUEL riERPONT LANGLEY. 
5 
ment of Allegheny observatory was rendered possible, and 
likewise the great discoveries in astrophysics by its director. 
At the age of thirty-five, in 1869, Mr. Langley published 
his first two papers, the very first being a report of two 
pages on the observation of the total eclipse of August 7, 
1869, at Oakland, Kentucky, and the second, “a proposal 
* * * for regulating from this observatory the clocks 
of the Pennsylvania Central and other railroads associated 
with it.” 
When we recall the intolerable inconvenience which at- 
tached to the changing of time in every forty or fifty miles 
of travel and the empirical method by which clocks and 
watches were set, resulting in annoyance, confusion, delay, 
and disappointment, these early labors of Mr. Langley, re- 
sulting in our standard time system and in the almost 
universal regulation of public clocks through electrical 
signals from observatories, must be counted, if not an im- 
portant advance in knowledge, a really great contribution 
to the convenience, comfort, and welfare of mankind. 
While these practical efforts to secure a fund for the equip- 
ment of the observatory were 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, Kentucky, resulting in the brief paper above re- 
ferred to, and in 1870 he accompanied a Government eclipse 
expedition to Jerez de la Frontera, which was under the gen- 
eral direction of Professor Joseph Winlock and included on 
its staff, besides Mr. Langley, Professors Young and Picker- 
ing, both of whom have since become among the foremost of 
American astronomers. 
Lie had meanwhile not lost his interest in the time service, 
the methods of which he described in an article in the 
American Journal of Science in 1873, proposing, in addi- 
tion to transmitting time to railroads, to supply it to watch- 
makers and jewelers and to cities in general for their public 
clocks. 
