^ 



Sect, IX.] 



METEOROLOay. 



291 



r 



minute, 2^ IS'"" 0% keeping the eye not on the watch, but 

 on the end of the rising column of liquid. At the 20th 

 beat read off, and register the reading (12'' -0), as in 



wait, watching 



column 3 A, of the annexed form. Then 

 the column of air above the liquid, to see that no blebs 

 of liquid are in it, or at the opening of the upper bulb 

 Twhich will cause the movement of the ascendinsr column 



tarts) 



the 



mill 



ate is nearly 



elapsed. At the 50th second begin to watch the liquid 

 rising ; at 55* begin to count 0, 1, 2, up to 20 beats, as 

 before, attentively watching the rise of the liquid ; and 

 at the 20th beat, or complete minute (2^^ IQ^ 0% read 





]m^ 



1. 



Date and times of 

 Observation. 



, 1850, 



Oct. 30. 



Initial. 



h. 



9 



m. 

 15 



16 



18 



19 



21 



22 



24 



s. 

 



30 

 



30 







30 

 



Terminal 



m. 



16 

 17 

 19 

 20 

 22 

 23 

 25 



s. 





 30 





 30 











2. 







eg u 





 X 

 © 

 X 



© 



X 



© 



3 



Readings of the 

 Instrument. 



A. ! B. 



Initial. ' Terminal 



+ 12'0 



45*2 



14-8 



28'0 



9-4 



t 



46-6 

 9-01 



+43-3 

 42-8 



48-2 

 26'8 

 43-9 

 45-5 

 43-2 



4. 



5, 



Ciiange - , 



pg^ Internal 



minute. '^^^^«^^' 



B-A. 



+ 31-3 



- 2*4 



+ 33* 



— 1- 



4-33 

 - 1 



4 

 4 



5 



E 



i! 



34*2 



75-5 



t. 



Remarks. 



The times r. re- 

 duced to appa- 

 rent timej or tc 

 the 3un*s hour 

 angle from the 

 meridian. 



Zero witiitlTawn, 



Blackened 



Tlierm. 106 '3. 



n i^ 



. 1 



) 



off, and instantly shade the instrument, or withdraw it 

 just, out of the sun and penumbra. Then register the 



reading off (43' -3) in column 3, B, and prepare for 

 the shade observation. All this may be done without 

 hurry in 20 seconds, with time also to withdraw the 

 screw if the end of the column be inconveniently high in 



o 2* 



