186 



changement d'inclinaison ne le comporle: donc du matin au soir, 

 il y a une augmentation reelle d'intensile dans le magnetisme 

 terrestre.« — ©patere unb »iel ialjlreidjere SBeobadjtungen in 

 ©reenivid), 93erUn, ^peter^burg, Toronto (Sanaba) unb ^obarton 

 (9San Siemen) ^aben Qlrago'ö iöeljauptung (1827) ber größeren 

 ^ortjontfll=5ntenfitflt «m 9(benb gegen ben 9:)iorgen beptigt. 

 3n ©reenwid) ift baö ^aupt:?ü?arimum ber Ijorijontalen Äraft 

 um 6", baö ^aupt=?l}?inimum um 22" ober 0-; in ©d^uljenborf 

 bei JBerlin max. 8", min. 21"; in <Peteröburg max. 8", min. 23" 

 20'; in Toronto max. 4", min. 23": immer in ber ^eit jeben Drtö. 

 (Siirp, Magn. Observ. at Greenwich for 1845 p. 13, for 

 1846 p. 102, for 1847 p. 241 ; mief unb 9??ofer in <poggenb. 

 2lnn. S8b. XIX. 1830 @. 175; Äupffer, Compte-rendu an- 

 nuel de l'Obs. central magn, de St. Petersb. 1852 p. 28 

 unb ©abine, Magn. Obs. at Toronto Vol. I. 1840—1842 

 p. XLII.) ©onberbflr abjveic^enb, faft entgegenfe^t, ftnb bie 2Berf)= 

 felftunben am aSorgebirge ber guten y;>offnung unb auf @t. ^clena, 

 n)o am 3(benb W y^orijontalfraft am f^n)a'c^ften ift (©a^ 

 bine, Magn. Obs. at the Cape of Good Hope p.XL; at 

 St. Helena p. 40). @o ift eö aber nid>t in ber ganjen füb(i(f)en 

 .^emifpl^are weiter in Often. »The principal feature in the diurnal 

 change of the horizontal force at Hobarton is the decrease of 

 force in the forenoon and its subsequent increase in the af- 

 ternoon« (©abine, Magn. Obs. at Hobarton Vol. I. p. LIV, 

 Vol. II. p. XLÜI). 



3^ (©. 104.) ©abine, Hobarton Vol. I. p. LXVH unb 

 LXIX. 



^« (©. 107.) a:otal=3ntenfitat in y;»obarton: max. 5"'/3/ 

 min. 20°V2; in a:oronto: y?aupt = ?Wat. 6", JC"»wpt = 9^in. 14°; 

 fecunb. ?War. 20", Ucmb. 9)?in. 22". SSergl. ©abine, Toronto 

 Vol. I. p. LXI unb LXII mit Hobarton Vol. I. p. LXVIII. 



" (©. 107.) ©abine, Report on the isoclinal and 

 isodynamic Lines in the British Islands 1839 p. 61 — 63. 



»« (©. 108.) .^umbolbt in «poggenb. Ofnnalen 95b. XV. 

 @. 319 — 336, 93b. XIX. ©. 357 — 391; unb im Voyage aux 

 Regions cquinox. T. III. p. 616 unb 625. 



ä» (©. 109.) ijtanfleen lUer ja'brlidK «Bera'nberung 

 ber Snclination in «poggcnb. 2lnn. 93b. XXI. ©.403—429. 



