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Monday, \%th March 1850. 

 The Right Rev. BISHOP TERROT, V.P., in the Chair. 

 The following Communications were read : — 



1. Note regarding the American Electric-Observing Clocks. 

 By Professor Piazzi Smyth. 



The object of this communication was chiefly to exhibit a speci- 

 men of the register of the electric chronograph, wherein the second's 

 beats of two clocks were marked side by side, one going nearly to 

 sidereal time, and the other to solar ; and the length of a second's 

 interval on the paper was so great, and the accuracy of the punctua- 

 tion such, that the minute acceleration of the one clock on the other 

 could be registered almost from second to second. 



The electric register can be applied with ease to any clock, and at 

 any distance from the recording apparatus ; and two or more clocks, 

 or they may be simple pendulums, can be made to register their vibra- 

 tions on the same slip of paper. 



The author pointed out how this method might be made available 

 for determining the density of the earth, by observations on the 

 shores of the Bay of Fundy, during the rise and fall of the enormous 

 tides which occur there. He likewise mentioned several purposes to 

 which Lieutenant Maury, U. S. N., proposed to apply the electric 

 chronograph ; amongst others, to determining the height of moun- 

 tains, as he thought that the accuracy capable of being attained in 

 determining the time of vibration of a pendulum in this manner, was 

 so extreme, that the method might be safely applied to such problems. 



2. Account of a Remarkable Meteor, seen 19th December, 

 1849. By Professor J. D. Forbes. 



I" On the evening of the 19th December 1849, whilst walking near 

 the southern part of Edinburgh, about fifteen minutes past five. 

 Greenwich time (as I afterwards estimated), I observed a meteor, 

 fully brighter than Venus at her average brilliancy, moving from 

 W. towards N., parallel to the horizon, elevated 15° above it, and 

 followed by a distinct luminous train. This angle was subsequently 



