transactions of the sections. 
53 
The general experimental results and the principles sought to be elucidated, 
were illustrated by a variety of references to actual cases of co p 6 
iron ships. 
fa Inquiry into the Principles and Measures on which Safety in the 
Suvigation of Iron Ships mat/ he reasonably looked for. Uy t te e 
W.Scoresbv, D.l)., F.P.S., Corr. Memb. Institute oj lranee, Qc. 
Thi? paper, interspersed with numerous illustrat've allusion?, was in substance as 
' lw*:—His time, Dr. Scoresbv remarked, was so limited in Ins paper on it o 
'■ hr ‘Tayleur/that he was obliged to leave off in the most critical position. e la 
i- out the disease, but was obliged to hasten to a conclusion with scarcely a 
Vri of consolation, or being able to offer any remedial advice. The result was, 
,ut a gallant officer then present said to him, “Why, vou have upset all our plans; 
) * hare told us compasses cannot be trusted. How are our iron ships to L’e navi- 
Show us the remedy! ' Thorn'll he, Dr. Scoreshy. did not admit the 
R’lOttitiility to give a remedy, it would be his object lu endeavour to point out ine 
• *? circumstances under which we may expect a fair measure of accuracy m 
guidance, and the circumstances to he watched againBt most eminently 
‘■Mated to produce compass changes. But before entering on these points, ne 
‘‘inportaut to revert, brieflv, to the leading principles developed in Ins long-niaae 
croons on the magnetism in iron, with reference to the compass action un.l its 
la hon ships. And this lie was the more encouraged to do, because of the 
'** fh,,n 8 c which hnd taken place in his position, as the suggoster ami promoter oj 
“ T Di ^ C l ,h ™°™na in this department, since his first paper on the subject 
t. ,' a lot ' ie British Association nt Oxford in 1847- ... 
"ow most gratifying to find, from the paper of Mr. Archibald Smith, a gen- 
,r.. e r nt a mathematician, and having all the records of Ucr Majesty s 
■,'JJ u con ‘passes, at command, that every essential principle, for which lie had 
ns . 10 the principles which affect the development and changes in 
■ Mr w£" ou . tU l*»* Emitted aud supported. These principles, soa pp^ 
-J (so far as he correctly understood his papei) be 
1 ™ a 8 neti ^ra of iron ships in its action on the compass, wayberepre- 
*. -r.wic It iiin Cr , ICa a “d a horizontal iron or magnetic bar swinginground , p 
«iSuri' 1*™::" xvhich -Dr. Scoresbv, had adopted some years a go, 
2. Tlnt’ri> S We la9 'n his publication of * Magnetieal Investigations, j . 
,|,! ch hy haci ang .?r * n t,ie raa 8 ne tic distribution and compass uctinn 
SW/" hic li\akc phice in a ship's magnetism by cl j a ^clre^tria~l 
Metier, tlle duc ‘ influence, theoretically assumed, g gb , g 
“Itriiuemg inferred from the Admiralty observations winch his, •* ; n 
6,111 to cu' .'sfactorily elucidated as a necessary consequence of 
t *' Thai ut,'“ rCK . ar f to the denomination of retentive magnetism. 
,n i!■' . art ‘ l "'fluonces in a ship, derived from the varieties of forraM p 
t0 the compass) of narticular musses of iron, winch »>a> act as 
5 ! “™ cora P aas ) of particular 
£ pf' an of correct ing the deviation of iron ships region! 
***•*»«, the ormr° r ,nufaa Vo V n e^> is unsafe, and in going to BOUtUer b 
11 or straining of the iron materials of a ship will tend, especially 
v/.'.That it to alter the magnetic action on the comp;-',|;,trihUtion, 
“ifk u ltimato?v lreSllmeto < -' ffoc 't the entire changes in a ship s magn ■ 
« e ne C ‘, i t J ma 7* in regions distant from the place of building, , ^ p r 
“ Id#d * a11 particulars'embodied and, 
r-v'u^ by S r 8 ? ,0 - n i B ' and now admitted and confirmed (as h® Scoreaby »s) 
’-•'.I?' a im 1 thevvff' i ea , VCB nolhin 8 of rpal oBJ^ 11011 lo establishment 
u-,i m, ' 03i tion nf m 6 f ' f the rcsulta P la,ul y 8°' hc Bclmves, to the tho se 
•U '‘ Ctl in the accu racy of which he has long endeavoured to con a ,, 
1UaUti «,cL„ lf tlon ofiron ships, that the niaguetisiuofsuch ship® * . 
’ Chan 9^hle ; the most enduring, or apparently fixed, being of a descr p 
