hich marked the edge of the sea ice and the place where open
water began. That was the _sena_ for which they were bound.

"Don't you think we'd better build our _igloo_ here?" Bobby suggested as
the others came up. "It's getting late and we can't do any hunting
tonight, anyway, and perhaps there won't be any good drifts out there."

"Yes, by all means," agreed Skipper Ed. "We'll have plenty of time in
the morning to go out, and if the hunting proves good, and we prefer to
stay there, we can build an _igloo_ at our leisure. If we get plenty of
seals we will want to haul them in here to land to cache them, and then
if the ice breaks up before we get them all hauled home, we can take
them in the boat. And while we are hauling them in here from the _sena_
we'll have a snug _igloo_ at each end of the trail, where we can make
hot tea, if we wish, and drink it in comfort."

They found an excellent drift in a spot well sheltered from the wind,
and because he was taller and stronger than Bobby and a better builder
than Jimmy, Skipper Ed, with a snow knife which looked very much like a
sword but had a wider blade, which was straight instead of curved,
marked a circle about ten feet in diameter upon the drift.

Then he cut a wedge out of the snow in the center, and with this as a
beginning he carved from each side of the hole blocks of the hard-packed
snow, each block about two feet long and a foot and a half wide and ten
inches thick. These he placed on edge around the circle, fitting their
ends close together by trimming them as he found necessary, with the
knife.

Bobby and Jimmy, each with a knife, now began also to cut other slabs
from a drift outside the circle, and passed them to Skipper Ed when he
had exhausted his supply within the circle. They were very heavy, these
blocks, and as much as the boys could manage.

When Skipper Ed had built a row of blocks completely around the circle,
he trimmed the first blocks which he had placed to a wedge, that he
might build his circle of blocks up in a spiral.

Each block of snow was so placed that it was braced against the one
next it, and its top leaned a little inward, so that as the walls of the
_igloo_ rose each was smaller than the one preceding it, until at last a
key block in the top completed the dome-shaped structure. As the house
grew Bobby plastered the joints between the blocks full of snow, making
its outside smooth like the surface of a snowdrift.

When Skipper