This would be quite feasible if the leaden messenger of death did not come in contact with the bone, for the bodies of the mammals were very soft and yielding from the amount of adipose tissue they contained.
These sealskins, with those which they had previously obtained, made up their quota to thirty.

The oil, likewise, extracted from the blubber filled up their remaining empty casks, so that they had now no receptacle wherein to stow any more should they succeed in killing more seals.

But, the brothers need not have troubled themselves on this account, for their last onslaught on the breeding-ground had the effect of the final straw on the camel's back, not one of the cat-faced animals--as Eric called them, from their fancied resemblance to old Mouser--being to be seen in the neighbourhood of the coast for months afterwards, albeit the young crusoes were constantly on the watch for them! Boiling down the blubber was, certainly, a tedious operation.
The brothers had made a rocky bed for their cauldron, near the hut, with an ingeniously constructed fireplace beneath it which had a cross-cut trench for creating a draught, in the way Fritz noticed that the soldiers made their camp fires during the war--the whole affair when finished looking like one of those "coppers" placed in back kitchens for washing days.

Over this laboratory, the two were busy enough for some days, making themselves so black with smoke and begrimed with oil that they resembled a couple of chimney sweepers, or engine fitters for the nonce! Eric, who superintended the details by reason of the superior knowledge which his whaling experience gave him, first cut up the blubber into long thin strips, which Fritz again subdivided into smaller portions with the aid of his sheath knife.

These strips of blubber were then heaped into the pot, under which a roaring fire was kept up, the operation being continued until the cauldron was full; when, as it came to the boil, the refuse matter and pieces of flesh adhering to the fat were skimmed off from the top, and the melted oil allowed to cool gradually, after which it was emptied into the casks kept ready by the side of the hut.
The brothers were very glad when the job was ended, for the blubber smelt terribly fishy and almost suffocated them with its fumes as the pot came to the boiling point; but, they persevered with their task until their casks were all full and headed up, when they proceeded to dress their sealskins roughly and salt them down in a large puncheon which they had reserved especially for their storage.
Next, they had a grand clean up, putting the hut and place in order, the blubber boiling having covered everything with a deposit of oily soot; and, the morning after they had made things comfortable again, they proceeded down to the garden to see how matters were progressing there, not having visited the spot since the day they had started on their last sealing excursion.
"I say, brother," observed Eric, as they directed their steps towards the little wood beyond the waterfall, where they could hear the thrushes chirping and whistling as they came near; for, the penguins were not so noisy now, having hatched their eggs and abandoned the nests they used to make such a fuss over.