SOME ASPECTS OF AMERICAN ASTRONOMY 73 



erected at Washington during the years 1843-44 and fitted 

 out with what were then the most approved instruments. 

 About the same time the appearance of the great comet of 

 1843 led the citizens of Boston to erect the observatory of 

 Harvard college. Thus it is little more than a half century 

 since the two principal observatories in the United States 

 were estabhshed. But we must not for a moment suppose 

 that the mere erection of an observatory can mark an epoch 

 in scientific history. What must make the decade of which 

 I speak ever memorable in American astronomy was not 

 merely the erection of buildings, but the character of the work 

 done by astronomers away from them as well as in them. 



The naval observatory very soon became famous by two 

 remarkable steps which raised our country to an important 

 position among those appl3dng modern science to practical 

 uses. One of these consisted of the researches of Sears Cook 

 Walker on the motion of the newly discovered planet Neptune. 

 He was the first astronomer to determine fairly good elements 

 of the orbit of that planet, and, what is yet more remarkable, 

 he was able to trace back the movement of the planet in the 

 heavens for half a century and to show that it had been ob- 

 served as a fixed star by Lalande in 1795, without the observer 

 having any suspicion of the true character of the object. 



The other work to which I refer was the application to 

 astronomy and to the determination of longitudes of the chron- 

 ographic method of registering transits of stars or other phe- 

 nomena requiring an exact record of the instant of their occur- 

 rence. It is to be regretted that the history of this application 

 has not been fully written. In some points there seems to be 

 as much obscurity as with the discovery of ether as an anaes- 

 thetic, which took place about the same time. Happily no 

 such contest has been fought over the astronomical as over 

 the surgical discovery, the fact being that all who were en- 

 gaged in the application of the new method were more anxious 

 to perfect it than they were to get credit for themselves. We 

 know that Saxton, of the Coast Survey; Mitchell and Locke, 

 of Cincinnati; Bond, at Cambridge, as well as Walker and 

 other astronomers at the naval observatory, all worked at the 

 apparatus; that Maury seconded their efforts with untiring 



