146 



Abstracts for the Vertical Force. 



TABLE XVI. — The Monthly Means of the Balance Magnetometer Readings, Corrected by a new value of q, 



for the Hours 20, 23, 2, and 5. 















Kange from the Four 



Month. 



201^. 



23h. 



2K 



5h. 



Mean of the 

 Four Hours. 



Hours for 















Each Month. 



Two Months. 



1841. 



Mic. DiT. 



Mic. Div. 



Mic. Div. 



Mic. Div. 



Mic. Div. 



Mic. Div. 



Mic. Div. 



July 



803-5 



813-4 



838-5 



861-6 





58-1 





August 













22-6 



40-3 



803-7 



807-4 



804-9 



826-3 

















39-0 



September 



723-6 



741-7 



749-2 



779-0 





55-4 



67-0 



October 



664-5 



691-8 



723-9 



743-2 



705-8 



78-7 



61-3 



November 

 1842. 



644-0 



664-6 



675-1 



687-9 



667-9 



43-9 















January 



983-9 



1000-0 



992-0 



1000-5 



994-1 



16-6 



23-8 



February 



964-0 



977-1 



974-4 



995-1 



977-6 



31-1 



25-5 



March 



926-3 



937-1 



928-3 



946-3 



934-5 



20-0 



35-5 



April 



904-9 



919.8 



930-6 



955-9 



927-8 



51-0 



32-7 



May 



918-2 



904-6 



906-7 



919-1 



912-1 



14-5 



15-4 



June 



895-0 



892-9 



885-3 



901-6 



893-7 



16-3 



34-2 



July 



856-6 



848-8 



858-7 



901-0 



866-3 



52-2 



44-4 



August 



856-0 



852-2 



855-5 



888-9 



863-1 



36-7 



37-7 



September 



837-3 



847-4 



856-4 



876-1 



854-3 



38-8 



35-0 



October 



816-7 



831-5 



833-8 



847-9 



832-5 



31-2 



35-0 



November 



794-7 



814-8 



825-5 



833-5 



817-1 



38-8 



26-6 



December 



782-4 



788-9 



793.0 



796-9 



790-3 



14-5 





The means for 1841 are not comparable with those for 1842 ; and of the months in 1841, only October and 

 November are comparable with each other. 



In the five months of 1841, the lowest reading is shewn at 20'^, the highest at 5** ; in August 1841, there 

 is a maximum at 23'', and a minimum at 2^. The force increases in the remaining four months from 20'' till 5"^. 

 In July, a minimum seems to occur after 20*' ; and in September, the force increases but slightly from 23** till 2*. 



In 1842, the highest reading is at 5''. In January, February, and March, a maximum occurs about 23'', 

 and a minimum about 2'' ; the lowest readings in these three months is at 20''. 



In April, and the last four months of the year, the readings increase from 20'' till 5''. 



In May a minimum occurs about O**, in June about 0'', in July and August about 23''. The minimum thus 

 seems to shift from January till June, and from June till December, occurring probably before 20'' in the winter, 

 and about 1'' in midsummer. 



The means of the four hours shew a continued diminution of the vertical force, which is irregular from 

 month to month. 



The ranges for each month, and for each two months, are irregular ; they shew, on the whole, an increase of 

 range in the summer compared with the winter months. 



The following Table has been formed from the above. 



i 



