Newcomb and Dutton — Speed of 



cients of the unknown quantities and not the absolute terms. 

 The distances from the centrum have been taken from the 

 Land Office map of the United States by measurement with a 

 scale. They are subject to possible errors as great as three or 

 four miles, but this error is so small in comparison with the 

 best times that the distances may be regarded as sensibly exact. 

 The following reports constitute the first group. For the 

 sake of brevity the full accounts of these reports are here 

 omitted. They will appear in the final work on the earthquake. 



Group I. — The best Observations. 



Time 9h+ 

 Locality. State. Distance. m. s. Weight. Observer. 



Centrum, S. C. 51 06 2 



Washington, D. C. 452 53 20 2 



Washington, D. C. 452 53 23 2 



Baltimore, Md. 487 53 20 1 



New York, N. Y. 645 54 30 2 



Dyersburg, Tenn. 569 54 00 1 



Prof. Newcomb 

 Alex. McAdie. 

 B. Randolph. 

 M. C. Whitney. 



Louis Hughes. 



From these observations the following equations of condition 

 may be formed. 



wt. 

 2 

 4 

 1 

 1 

 2 



- 2 



+ 1 

 +13 



- 



- 7 



x + Oy = 



x + 452y = 135-5 



x + 487y — 134 



x + 569y = 174 



x + 645y = 204 



By the process of least squares the normal equations are : 



lOsc + 4154 = 1258 



4154a + 2210196 = 672408 



The solution is, x '= — 2'6s + 4 -7s. and y = 0-309 ± 01. 

 The resulting speed is, 3*236 ±0105 miles or 5205 ± 168 

 meters per second. 



Group II. — Gc 



od rep oi 



'ts, giving the time of beginning to tht 





nearest minute 



or half 



minute. 





Locality. 



State. 



Distance. 



Time. 



Weigh 



Observer. 



Centrum, 



s. c. 







51 m 06 s 



2 





Nashville, 



Tenn. 



43b 



53 30 



1 



J. D. Leonard. 



Covington, 



Ky. 



488 



53 41 



1 



Jos.Brookshaw 



Pikesville, 



Md. 



490 



53 30 



1 



C. R. Goodwin 



Evansville, 



Ind. 



545 



54 



1 



F. W. Norton. 



Cleveland, 



O. 



604 



54 



1 



Wm. Line. 



Cleveland, 



O. 



604 



54 



1 



G. H. Tower. 



Crawford sville, 



Ind. 



620 



54 



1 



E. C. Simpson. 



Belvidere, 



N. J. 



622 



54 



I 



G. W. Holstein 



New York, 



N. Y. 



645 



54 30 



1 



N. Y. Herald. 



Stockbridge, 



Mass. 



765 



56 



1 



"2" 



J. O. Jacot. 



Albany, 



N. Y. 



770 



55 



1 



W. G. Tucker. 



