28 Description of a new Compensation Pendulum. 





Error of clock 



Number of d 



ays 





1806. 



at time of ob- 



between the 



ob- 



Daily rate. 



servation.. 



servation. 









S. 







5. 



March 2 ! 

 April 8 



00 



Fast 2*8 



is 



32 





' Gain 0-15 

 Loss 0'33 



May 1 



Slow 8*7 



16 





' — o-so 



26 



— 21*5 



26 





— l'lO 



June 2 1 



— 50 









Increased the compensation for heat and cold 6 holes 

 equal to 4 inches and 3 quarters; or, .the length of the zinc 

 bar 25 inches. The clock was agaih set to mean time. 







s. 











s. 



July 1 



Slow 



O'O 





26 





Loss 



0'3« 



27 



9-3 





13 







0*21 



Aug. 9 



i' j 



12-0 













* j -^j-j» «7 









7 





r- . ., 



0*31 



16 



■ -- ■ 



14-2 













Sept. 13 



— 



24'0 





28 

 12 





z 



0-34 



0-80 



25 



P i 



35'5 













Oct. 17 



— 



52-1 





22 





'■ '" 



0-84 



Although a thermometer 



was 



attached 



to 



thecl 



ock, I 



could not, from a necessary attendance to business, register 

 it regularly. The difference of its height in March and June 

 may be taken at about 22 degrees, and in July and October 

 14 degrees, without much error. 



On comparing it with the rate of the clock, the compen- 

 sation, in the latter case, appears nearly as much too great, 

 as it was in the first too small. The true length of the zinc 

 bar ought to be about 23 inches. 



The length of the zinc bar, thus ascertained, is one inch 

 and three quarters more than the experiment by the lamp 

 makes it : indeed, I have always suspected there might be 

 some error in that experiment, on account of the length of 

 the arc of vibration being affected by it. 



Having no means of findiug the time accurately but by 

 equal altitudes, I could not get so many observations as 

 might be wished. I trust, however, these will not be found 

 altogether useless. I am, sir, your obedient servant, 



Henry Ward. 



Blandford , 

 October 21, 1806. 



To C. Taylor, M.D. Sea. 



A Re- 



