140 



MR. R. D. OLDHAM ON THE PROPAGATION OF 



The time of commencement of the record at Nicolaiew is obviously late, and 

 corresponds rather to the maximum than the commencement of the first phase. 



Converting these times into intervals, and distinguishing the earlier shock as (1), 

 the principal one as (2), we get 



2. ARGENTINE, October 27, 1894. 



According to an account of this earthquake by A. F. NOGUES,* the zone of greatest 

 intensity formed an ellipse whose major axis passed by Rioja, San Juan, and Mendoza 

 while the minor axis reached nearly to the foot of the Andes. The epicentre may be 

 safely placed in S. lat. 28 30', W. long. 69 0', with an error of less than 1 of arc. 



The time of origin is not so easy to determine. It was recorded in the observatory 

 of Santiago de Chile at 4 h 7'" 40 s P.M. local mean time. I have not been able to 

 obtain the exact meridian of this observatory, but it is, according to the best 

 atlases, about 2 m east of Valparaiso, whose local time is 4 1 ' 46 '5" 1 slow of Greenwich. 

 Applying this correction the G.M.T. (civil) at Santiago becomes about 20 h 52 m . The 

 only other time observation of any value is that from Buenos Ayres, where it was 

 recorded at 5 h 2 m local time, which is about 3 h 53 '5 m slow of Greenwich ; the time at 



Comptes Rendns,' vol. 120, 1895, pp. 167-170. 



