1825.] Variatio7iof the Mariner's Compfiss. ^ 



A table of the progress of the magnetic polfe as derived from 

 the dip and variation observed in London in the year 181?;'" * 



Number of Years. ^ . ^^l^ JAij^^ ixiU.W^dl "H: 



2 1 15 46 22-4^ 



I 2 '? 32 IIS r-^-^-^^ 



4 2 ol o-^ 44*oo i.,j ffnhffA T ! 



5 3 09 -25 56-10 ^..l^iriq 

 -^- l-^-V.fV.3 47 19 07-32 .,1, ,i m 



T 4 25 12 18-54 s^r ot. 



8 5 03 05 29-76 



9 5 40, 58. 40-98 UaiftoC) J 

 10 6 18 51. 52-2Q,, . . o 



1 month 03 09 25-93— ^^'«o^^ ^^ 



Progress of the magnetic pole accordingiaacjSi^ai* between 

 that deduced from * 



1. The annual precession of the nodes of Venus and of the 

 earth. « ; m ^ 



2. The tropical re volutioii of Venus andrtheeartEf^^' ^^" 



3. The period of eclipses. - ta -^j 



4. The Dyonisian peri6d formed of thesoiafi^dltiMrCjycles. 



Number of Years. ' ^ '•' ■ ' «• .vVT in*"! ? 



1 ... .,.0^.38' 20^ 47-^2!8^^^-*''^' 



2 M^-^^1^16. 41 34-56,. _ 



■ ^ H^r -ra. ^t^ti09i'a55,.,02 . 2i-84.^;^^^-^^;r. .8 



4 2 33 23 09-12 



5-de ^V 3^ 11 43 56-40 



6 0^ (>l^3 50 04 43-68 



■7 oQon^.Q 28 25 30-96 . .^^^ ^„.p 



8 ^?^^jl^06 46 18-24 f^^'''^ 



9 ?;^Pt45- 07 05-52- '^^^ :^^£ i 

 10 ^Qvbtig'. 23 27 52-80 ' ' ' '* ^^"^' 

 50 Z^:Wt&7 19 24-00 



100 '' 63 54 38 48-00 m^ ..^ik;'-) 



" I ^ ^- 1 month 6 3 11 4^814 ^T -^"^^ 



The whole revolution in 563-28 years, which is very nearly 



the period of ecHpses, and may probably require to be reduced 



to it to be perfect. A few examples calculated according to this 



table will leave little doubt of its being nearly correct.'' oS yC "^'- 



^fioi 8ii '^So i 

 8d^\8io^^l^S^^°^Gb9b-. 



London, 1812. 



