1835.1 



on the Height of the Barometer. 



253 



pression in any particular spot must have the effect of producing an 

 elevation somewhere else," then, we may see why in any one place 

 (taking the year throughout) the maximum elevations and minimum 

 depressions on the same days of the moon's courses coincide, &c. But 

 it is straving from the subject, to attempt to reason upon phenomena, 

 while we are as yet only in the threshold of our inquiry. 



In pursuance of the idea I have above mentioned, I next took the 

 maximum elevation that occurred in each successive division of 5° of 

 the moon's distance from the equator in each year, and then took the 

 general average of the whole 10 years. I did the same with the 

 minima, and obtained the following General Average. 



Declination 20° 15° 10° 5° 0° Equator. 



Bar. max, inches 30'032 

 Do. minima, . . 29"236 



•033 

 •313 



•026 

 •355 



•026 

 •379 



022 

 •375 



Inches, 30-000 

 •90O 

 •800 













Maxima. 































.. . 



•700 













•600 













•500 













•40o 













•301) 

 29-200 























These two series of numbers would very nearly form two curves, 

 with their convex surfaces to each other, thus : 



[We are sorry to perceive that 

 the diagram which was copied 

 from the rough sketch in the MS. 

 without advertence to the text, 

 does not faithfully represent the 

 figured statement ; but theauthor'a 

 intention will be easily under- 

 stood. — Ed.] 



I will now leave this part of my subject, as I shortly expect some 

 further Registers and Nautical Almanacks for comparison, and I will 

 hereafter revert to it more in detail, and make out a Table more at 

 length, shewing the results of each year. 1 have brought it forward 

 now somewhat prematurely, because from sickness and consequent 

 removal from home, my labours must be suspended for some months, 

 and I am desirous before that happens, to bring forward the following 

 note, which 1 humbly hope may not be without its use to a large and 

 important class of the community. This was the end which I pro- 

 posed to myself in commencing a long and laborious investigation, 

 and, if I attain it, in any degree, my purpose will have been more or 

 less answered. 



Notk. 



Shewing, that the greatest depressions of the Barometer do not, fas 

 some have conjectured,) coincide with the days of conjunction and oppo- 

 sition of the moon, neither with the daijs of her perigee, hut that they 

 coincide, or nearly so, with the days of her maximum monthly declina- 

 tion. 



For Example. 



In the tea* years of which the barometrical daily changes have been re- 



* The ten years alluded to are: 1823, 1826, 1827, 1828, 1829, 1830, 1831, 

 1832, 1833, 1834. 



