506 
number of nippings which are not sufficient to 
directly crush the vessel, while the same num- 
ber of equal pressures on its iron companion 
become slowly accumulative, until it finally 
succumbs. 
A wooden vessel, however, may be very 
properly plated with iron over the hull for 
some feet under water, to protect it from the 
grinding action of the ‘ ice-tongues,’ which are 
formed by the unequal melting of the edges of 
large ice-cakes, which, projecting their huge 
submerged points often for a distance of twenty 
or thirty feet, become dangerous to a vessel 
compelled to thread narrow and tortuous chan- 
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in such a tremendous pressure, she could be 
saved in no other way. Therefore, when a 
‘nip’ is inevitable in a narrow ‘lead’ con- 
stantly closing down on a vessel, this fact 
should be strongly borne in mind in selecting 
that point where the least damage will probably 
be done when the final collision comes. It 
would appear, therefore, that iron ships are infe- 
rior to their weaker but more elastic wooden 
compeers; and this is ably demonstrated by 
facts in the sad fate of the River Tay in 1868, 
in Baffin’s Bay, and of the Swedish exploring- 
ship Sophia, in the north of Spitzbergen. In 
both instances these vessels sank under cir- 
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Fic. 1.—Cross-section of Jeannette. 
nels and ‘ leads’ in an open field of pack-ice, 
where the first intimation of their presence is 
a low, dull, groaning sound, and a swinging 
of the ship, probably a half-dozen points, de- 
spite the helmsman, or probably a perfect arrest 
as the helpless ship comes up broadside against 
the cake of ice, and with all sails thrown aback. 
‘Ice-tongues’ which gradually shoal from a 
greater depth than that drawn by the vessel 
are not so dangerous as those not so deep, the 
latter acting like a ram ina collision. In case 
of a ‘nip’ or a pressure from ice on both sides, 
these same ice-tongues are to be earnestly 
prayed for, as their shoaling sides often aid a 
vessel in being lifted out of the water, when, 
cumstances where good wooden vessels would 
probably have survived. 
I believe the limited experience with iron 
rigging in the arctic regions has been against 
it, except on short summer cruises with no in- 
tention of wintering. However, it is not a 
subject of much importance, unless the sails 
be alone depended on. 
Coppering is of little or no use, and I have 
not been able to find any comments upon it 
by those who have used it. In such cases. it 
was probably a part of the sheathing before 
the vessels were intended for arctic duty, as 
on the Erebus and Terror. The fact that most 
vessels are sheathed with two or three inches 
ets s Ate a Rae 
64, 
