510 
that a dark-colored kelp-stalk over twenty feet 
long had cut five feet into the solid ice a crevice 
not over an inch or two wider than the stalk, so 
that it was impossible to get it out. 
The difficulty of sawing increases in a rapid 
ratio with the thickness of the floe; and, when 
its depth becomes so great as to allow a play 
of but a foot or two with the ice-saws, it be- 
comes essentially impossible. Ice-saws, if very 
thick, impose severe labor on those operating 
them, by their great weight: if thin, they will 
warp and cramp in the thick ice, also creating 
severe labor. As all these contingencies can- 
not be foreseen, it is desirable to have a con- 
siderable assortment of these utensils, varying 
in length and weight. I think a description, 
however short, of ice-saws, is hardly needed, 
but will briefly speak of the ways I have seen 
them used. A ‘one-man saw,’ like the same 
named article in timber-sawing, can be used in 
ice up to four feet. Another foot, or even to 
work effectually in from three to four, requires 
two men, as shown in fig. 8; and it is evident, 
that, as the labor increases, the force at the 
bar can be increased, if the saw is only strong 
enough. As the floe gets thicker, the saw 
must be larger and have greater play, to work 
effectively ; and this 
soon gets beyond 
the power of men 
and the reach in 
their arms, and a 
tackling is rigged, 
as shown in fig. 9, 
which can, I think, 
be understood with- 
out explanation. If the weight of the saw is 
not sufficient to pull it down, with the push- 
ing assistance of the two men, its submerged 
end must be loaded with an anchor or anvil. 
A small funnel-shaped harbor, with but few 
projections along its converging sides, may 
sometimes be relieved of all its ice at one time 
by a small amount of sawing along these ser- 
rated edges, and a happy combination of tide. 
wind, and good management. ‘This is espe- 
cially the case where the rise and fall of the tide 
exceeds the thickness of the ice, the consequent 
vertical oscillation of the ice keeping it broken 
up in hummocky masses along the shore-line. 
The use of blasting-apparatus has, so far, 
been of but little use; still I think a series of 
small charges, fired electrically, giving rather a 
pushing than a splintering concussive effect. 
might be used advantageously in removing 
quite large masses of obstructing ice favor- 
ably situated. 
he more efficacious in harbors not fed by fresh- 
Kie. 8. 
SCIENCE. 
Blasting, I believe, would also - 
” 
[Vor. IIL, No. 66. 
water streams, as here the ice is more brittle, 
less tenacious and’ elastic, and consequently 
harder to remove by the percussive power of 
explosives. | 
A sailing-vessel can wait almost until she is 
liberated by the forces of nature, as this will 
probably be the earliest date that she can use 
her peculiar motive power effectively. 
Even a good harbor may have its disadvan- 
tages for a ship, if she has entered it during an 
exceptionally open season; and, unless this 
recurs within the time for which she is pro- 
visioned, she must be abandoned to save the 
lives of the crew. McClure’s Investigator in 
the Bay of Mercy, in 1854, is an example of 
such necessary abandonment. 
The use of balloons to make slight ascents, 
— they being made fast to the ship, — to en- 
able the ice-master to obtain a more compre- 
hensive view of the state of the ice, has never 
yet been experimented with, though by many 
recommended, and consequently can be neither 
rejected nor accepted as an auxiliary in this 
sort of cruising. Certain it is, however, that 
nothing is more deceitful at times than ice- 
‘packs or ice-drifts at a distance; the most 
invulnerable-looking, upon a closer examina- 
tion, proving to be the most disjointed, and 
the reverse. No arctic ship, of course, will be 
without her ‘ crow’s-nest’ of the whalers, —an 
elevated ‘ lookout’ on the foremast, with good 
protection from inclement weather, for her ice- 
master. 
The advantage in having two ships over one 
is apparent. It proved the salvation of Parry 
on his third journey, and other instances are 
not wanting. ‘The benefit of two crews to cut 
in or out of harbor, and in other work where 
it is the same for one as a dozen vessels, is not 
to be overlooked. 
