45(3 



Analyses of Books, 



[Dec. 



and when in the open air,* which Mr. Christie also noticed, and 

 stated, in a former paper, his opinion that they had arisen from 

 the difference in the changes ot temperature in the magnets in 

 the two situations, are next investigated in the memoir before 

 us ; observations on the temperature of the magnets having 

 been made in the open air, corresponding to those made in doors. 

 We select the subjoined tables from among the results of this' 

 branch of Mr. Christie^s inquiry: 



{7th and \%th June, 1823. 



Mean temper- 

 ture of the 

 . magnets. 



.Magnetic in- 

 Dilf. of temp-i tensity, or va- 



60-2i> 

 68-25 

 74-60 

 61-75 

 73-60 

 55-S8 

 66-00 

 73-60 

 56-90 



in successive 

 observations. 



lue of -—. 

 M 



224-0981 

 222-8171 

 221-7046 

 220'7198 

 222-3967 

 220-8778 

 222-6462 

 221-2655 

 220-1532 

 222-5146; 



Variation of 

 F 



-- for 1° Fah. 

 M 



F 

 M 



0-1179 

 01391 

 01551 

 0-1305 

 0-1260 



0-1315 

 01461 

 0-1314 



00! on J 



18 

 • 8 



la 



.rtooVl 



im, \my 20th,M224imJie, JS^t^ ^| 



]\Iean temper- 

 ature of the 

 magnets. 



DifF. of temp, 

 in successive 

 observations. 



55-400 



7380 



55-40 



55-45 



64-30 



73-90 



64-28 



55-55 



65-15 



66-75 



5065 



55-80 



51-35 



57-20 



54-08 



61-35 



55-94 



+ 18-40 

 -18-40 



8-85 

 9-60 

 9-62 

 9-73 



11-60 



+ 5-15 

 - 4-45 

 + 5-85 



2-73 

 4-59 



Magnetic in 

 tensity or va- 



F 



lue of — . 

 M 



222-8859 

 220-6103 

 222-9113 

 222-5640 

 221-4144 

 220-0549 

 221-3962 

 222-4610 

 222-7217 

 221-3013 

 222-9322 

 222-3848 

 222-8660 

 222-2080 

 222-5974 

 222-9263 

 222-4377 



0?. 



08 



0?. 



Variation of- 



'I . J' -n- ' )^o Of biT 



0-1237 

 01251 



0-1299 

 01415 

 0-1394 

 0-1220 



01224 



01063 

 0'1059 

 0-1125 



0-1203 

 0^1064 



bsuniji 



• These anomalies are described by Mr. B. in his paper on the daily variation of the 

 horizontal and dipping needles under a reduced directive power, of which an abstract 

 w«8 given in the Annals for March, 1824. 



