22 
REPORT— 1847- 
evcoing; the deflectioo then commenced to the left-hand, increasing to aboitii 
night —then returning, became vertical again ind)e moruiog; and the next 
forming, with trifling irregularities, the same course, and this was found tortcjtrm 
day during the fortnight the observations were continued. It is thus raidfnd 
Tiuua that, from some cauac still to be discoTffwl, a enrrent of ekcthalrfM 
during certain hours of the day along the wire andtiimugh the cuilin oaetotM, 
and for the remaining hours in b reverse direction. It appears also that tie b 4 
and cootacti were so arranged, that when the needle was deflected to lit Mtk 
direction of the current waa such that a horizouial needle plated above tk*i» 
would (from tlie electric influence uf the wire) liave its north end defitcUdtiit 
c«l ; and of course when the deflector was to the right, a horizontal needle*dalf 
situated would have its north end deflected to the west. It follows tbensfiiRih 
^^*tractcr of the current passing along the wire from north to south durii|fli 
midday hours, may be represented ^ a current passing from the coj^r to (ka 
pole of a batter)’, and during the miduight hoars from the zinc to the capietjth 
lue next question is, is the earth-connexion necessary for the altamn^otft* 
results ? To teat this question, the wire was disunited from the 
mity, m which case no motion could be detected in ibe needle. 'Ibewift™*^ 
connected with the earth at one ertremitv only; but still do mottou ww 
A complete circuit was then made of ei|^ty-two railea, by tiaitiog twowiw**®’ 
minghiun, but still wiibnnt effect ; but in every instance motion was saffici»bj» 
servable when the extivmities wore both in connexKinwith the earth. 
4 author concludes that the currents ai-c on theetrth'sstrw 
and that they flow spontaneously and alternately as in the wire itself, whidik^ 
poses l^roni its eartli-connexioTis to participate in the general conduction, of 
l!L**T* ^ <iuantitica, but which become very observable when the amounthin^^ 
y the coils. Moreover, as the times of vcrticalitr or of non-aclioo on tt« 
m^r, and the times of maximum lutensitv, ftcrwso nearly with the times of cb^ 
and mMjroam deviation in ihr daily motion of the horizontal needle; 
currenti on the earth's surface would, from tho known laws of elretro-ms?'^*"' 
P^ucp such horizontal deviations, he still furtiier concludes that the tiro ^ 
roena are mtimatdy connected, and that there is strong prcsnmptive evidf8«i» 
‘^"I'Jdiate cause of the diumid variation. Since the di*»^ 
sivdnii r.r ^ action between a galvanic corKlnctiog-wiie anil 
•wml of the phmnomenn due to terrestrial magnetism have been 
eipcf rlr. ** ®***^®^® of terrestrial electrical cuneots; and since the discowvy*^'^^ 
ciwnc by Secback. the sun has been considertd as tlie ptobaHt 
<;urrcnts niigbt be proiluccd ; but this I believe is the first 
Th JI pt-acHcally exhibited. ^ 
tion observations open a new and interesting field 
in diffe^n?. ,v^V/ectually pursued by the cordial co-operarion 
iuch cn^V.^T''^r- secure, what is the actuid 
or have thrv nni.^7 ^‘‘“‘‘ctlv north and south from the poles to 
obscrvatlnnl wngnctic meririi-ans? The lines 0“ 
totceptbn of Derby and 
Er^thT^SiiStl t but it w’ould be interesting to •‘ceztamwb*^^ 
Varmoutb ai- nnd wmst line, ns for Instance fnta 
wTm •>“ the Sonth-Easteri, line, 
BTcatlv tn rbn nB*l***u »Derby to Lincoln inehn®*< tu. ^ 
meotiM hv M n’ i*”^ stated in the conversation which H»k 1*^^ 
medial.. v»... ~ ' "le Relieved, if he cottid Dare sww'^ 
that Urn ‘1‘^tectod. jodging from tbenro^ 
Of the TcIcCTanh (' liberal manner in which Mr. Hatohcr, 
•«tvea no dSALT.f^"-’^' conceded the use of the Company’s 
facility to unv PT..ifi« <^<>topany, as also any railway company, woaW 0. 
reclion, for tlio^, conveniently situate’d near a line, having ony derirol* 
' " "ivcstigation of this highly interesting inquiry. 
