TRANSACTIONS OF THE SECTIONS. 
49 
the definition of high powers, if we did not remove as much as possible above all 
twh interferences as fogs, sounds and the like. From his own observations at the 
height of 600 feet, the fogs began rapidly to disappear, and to afford much clearer 
vision through the atmosphere. 
Navigation. 
On the Loss of the ‘ Tayleurand the Changes in the Action of Compasses 
in Iron Ships. By the Rev. W. Scoresby, D.D., F.R.S. Sfc. 
There were perhaps few subjects, he said, of more practical consideration and 
^i'ortance than the one which lie had the honour of submitting to the bection on 
that occasion; and if of more importance and consideration in one p ace in 
^'ther, he might say the port of Liverpool ought to stand pre-eminent in respect 
'he consideration due to compass guidance in iron ships. . 
importance of determining not merely the principles which occation tne 
>nnl development of the magnetic condition in iron ships, hut also of deter nu g 
11 principles upon which changes in that development would take place, >'• 
proportionate to the extent to which iron was employed m the cona^Rchon 
wl* navigating the ocean; and so great had been the increase m the adoptiODM 
: ; “, a "‘“ferial for ship-building, that in raudY ports where they were««U6t^ed 
, Jodd a large number of vessels, it would be found that nine-tenths ot ™ves 
/ r ,'" n " were entirely vessels of iron. I Ic did not know but thatprc-cminence ot pro 
ia might exist here ; but, at all events, the application of iron as a 
'rtrd „u CI l D sbi P a was rapidly increasing. There were certain P” P oge 
■ with the navigation of iron ships which were universally admitt ■• 
’ a m r re ; lbat iron » being more especially disposed to the magtie > ^ 
material, of course, calculated above all others to disturb the ect | j 
_ ^ on board the ship. Again, it was also admitted, that there weredifficulbea 
■ l,w navigation of iron _* n »i of the original or pnninr , 
i"''iUv in ocenncid as mysterious—changes wun-u , t0 bH ve ry 
r 1 ascrrtn- gar i d t0 T 8b 'P B w hosc magnetic condition had been »«1'P' ))e was 
■ ■ d to lT ed ' 11 would bc the leading objects of the 
: - Condi?! e ’ to 'Endeavour to develope the principles on which b V g an(] c j,._ 
• stances ir .°. n , sbi P s was distributed, arid to show the ’ mc j , ancho |y ca se 
' lf 'Tavlpn^ * bl . cb clm 'igcs must necessarily take place. Th nect with 
' Cinoral | Ur apordcd an example of the most impressive i“ od . nnaht not 
4S 0 a anng of tbls important subject. A. many of the Sec two ■ 
^til^'Sj^c'rcumstences connected with the wreck, he would sketch y 
- 11; shin . T essa, 7 t0 carry on the subject. Liverpool on 
n,!j -*’dtiy ,i o;l eur> a new vessel. bound to Australia, sailed t burt hen, 
! W'ny nf tbe P rcsent y ear - SheW! l S l?heSa"clpas- 
1 r - altouDii anf &bu bad on board about 458 passengers, , , on 0I 
! v -neatest*!* * <»««l ..f 528 ,»«»., She loft l£. ^ 
- u iu ft map, wmen ne saw . 
Co urse " 0 f 5 E' Vl1 ' * QW8on » ami which illustrated the positions ne \l‘"' t | u , r; and 
■° u * eight o’ci P a P L T.]—■On Friday she encountered very Y ^ g fBt time 
^rtained tliatth, 0 " ^ f,j|,owin B (Saturday) morning i tw ass( , £ . There 
.1 rt ' three co Cre ' v aa a material difference between the P . One of 
;i , ^C2 a r l S °i n b0ard ’ bllt be wouUI 0Dl >' r fC 'v°„ tW be LSS'i a" d tbe 
c / r the helmsman, and was the one by which he jg ca i| e d, 
by - be ,nizer >ma»t. Both of these compasses had bee■ , j bcen 
2> , *W52fi eat “■***»* flo tbat iM1,c 
. ' ', 10t have changed or differed from each othen 
1854. P455uea r the helmsman, the captain had the idea firmly .inpressea v 
