May 20, 1887.] 



SGWJSrCE. 



499 



At distances greater than six hundred miles, the 

 difficulty of associating the time records with 

 particular phases of the shocks becomes very 

 great. In most cases the motion was the swaying 

 movement, with only faint tremors of the rapid 

 kind ; and those who felt them were slow in rec- 

 ognizing their character. Readers must form their 

 own opinions as to the degree of approximation 

 to the time of the earliest movements, from the 

 following records. We give them only as we 

 received them, without attempting any discus- 

 sion. 



J. O. Jacot, watchmaker and jeweller at Stock- 

 bridge, Mass. (772 miles), was sitting by his regu- 

 lator-clock, distinctly recognized tlie nature of the 

 movement, and noted the time as 9.56. The phase 

 of the shock is uncertain. 



At Albany, N. Y. (772 miles), Mr. J. M. Clarke, of 

 the New York state museum of natural history, 

 heard the mortar falling down the chimney and 

 the creaking and straining of the building. As 

 soon as he appreciated the character of the dis- 

 turbance, he noted the tfme by his watch at 

 9.56.30. He did not ascertain the error of his 

 watch. In the same city. Dr. Willis G. Tucker 

 says he instantly looked at his watch, and after 

 comparing it next morning with the time of the 

 Dudley observatory, and making correction of the 

 error, gave 9.55 very nearly, with an error proba- 

 bly not exceeding twenty seconds. 



From Fonda, N.Y. (780 miles), Francis L. Yates 

 reports 9.55 (no particulars). 



At Ithaca, N.Y. (695 miles), the regulator clock 

 on the wall of the railway-depot stopped at 9.55 

 ' exactly.' 



At Gowanda, N.Y. (666 miles), where the shocks 

 were faintly felt, W. R. Smallwood, watchmaker 

 and jeweller, noted the end of the perceptible 

 shocks at 9.55.30 by his regulator-clock. 



At Toronto (753 miles) the earthquake was re- 

 corded automatically upon the magnetographic 

 traces in the observatory of Prof. Charles Carp- 

 mael, superintendent of the Meteorological service 

 of Canada. In his letter of Sept. 14 he says, " I 

 may state that at 9.55 p.m. all our magnetic needles 

 were set in motion by earth-tremors. The vibra- 

 tions of the magnets continued for about four 

 minutes. I would say, that, from later and more 

 careful measurements from our magnetic curves, 

 I make the time of the earth-tremor at Toronto 

 to be 9.54.50 p.m. standard : this time, I should 

 say, would not be astray more than a few sec- 

 onds." As this record was automatic, and gave 

 not only the time but the phases, it has been 

 thoroughly investigated by Professors Nevvcomb 

 and Carpmael, assisted by Mr. C. A. Schott of the 

 U. S. coast survey. The final result of this re- 



examination is to change Professor Carpmael's 

 computation to 9.56.18 for the beginning of the 

 tremors, with a probable error of fully one minute. 

 This large probable error is due to the very small 

 scale upon which the magnetograph records time 

 intervals (one-tenth of a millimetre corresponding 

 to twenty seconds), and to want of sharpness in 

 the photographed traces. This time gives 2.66 

 miles per second, or 4,250 metres, with a probable 

 error of one or two tenths the amount. 



The clock in the Western union telegraph office 

 at Pittsburgh (523 miles) was stopped at 9.54. 



From Cincinnati and suburban towns (500 miles) 

 come many reports. In this city, local mean time 

 is largely used, owing to the fact that it is nearly 

 midway between the 75th and 90th meridians, 

 where the only inconvenience of standard time is 

 at a maximum. The correction to the 75 th me- 

 ridian is 37m. 40s. The Western union telegraph 

 office gives 9.54. The Times-star newspaper gives 

 from the clock in its own office 9.16 'exactly' 

 (9.53.40 standard); at the Commercial gazette 

 office, 9.17.45 local, 9.55.25 standard (probably 

 noted after the shocks were over). At the fire- 

 tower after the principal shock, 9.16 17 wasnoted ; 

 clock error twenty-three seconds slow, giving 

 9.54.20 standard. Two other observers noting by 

 watches give 9.16, and one notes an advanced 

 stage of the shocks at 9 17, but they give no 

 means of estimating their errors. At Covington, 

 Ky., across the Ohio River, I. J. Evans, watch- 

 maker and jeweller, reports his regulator-clock 

 stopped at 9.17.20, Cincinnati local mean time; 

 phase of shock unknown. 



From Craw fords ville, Ind. (622 miles), E. C. 

 Simpson, C.E., reports through Prof. J. M. Coul- 

 ter of Wabash college, "Suddenly felt my chair 

 move, jumped up, and said, ' We are having an 

 earthquake.' At once pulling out my watch, I 

 found it was 8.54 p.m., standard time (central). 

 Professor Coulter adds, that the watch was 

 exactly with railroad time as shown at the rail- 

 road-station and also by the town-clock. 



From Dyersburg, Tenn. (569 miles), Louis 

 Hughes writes, " My time-piece vs^as an English 

 patent lever watch of Charles Taylor & Son, Lon- 

 don, which from business necessity I keep closely 

 with railroad time at the station, which receives 

 the time at ten o'clock every morning. The rail- 

 road uses central time. My first thought was that 

 the shaking was caused by the children in the 

 next room, but in the next moment, recognizing 

 the peculiar sensation, I dropped the newspaper 

 and observed the time, which was probably from 

 four to six seconds after 8.54, and from that ap- 

 proximated it in even minutes." Speed 3,25 miles, 

 or 5,230 metres. 



