-birds had nested. Cape pigeons, the rare
silver-grey and snow petrels were all present. Amongst these Laseron
made a collection of many eggs and birds.

The traverse-line was then carried back to Madigan Nunatak along a
series of connecting mounds. After being held up for three and a half
days in a blizzard from December 31 to January 4, the party were home
once more late on January 5, 1913.

Returning to the fortunes of the air-tractor sledge, which was to start
west early in December. Bickerton has a short story to tell, inadequate
to the months of work which were expended on that converted aeroplane.
Its career was mostly associated with misfortune, dating from a serious
fall when in flight at Adelaide, through the southern voyage of the
'Aurora', buffeted by destructive seas, to a capacious snow shelter
in Adelie Land--the Hangar--where for the greater part of the year it
remained helpless and drift-bound.

Bickerton takes up the story:

I had always imagined that the air-tractor sledge would be most
handicapped by the low temperature; but the wind was far more
formidable. It is obvious that a machine which depends on the
surrounding air for its medium of traction could not be tested in
the winds of an Adelie Land winter. One might just as well try
the capabilities of a small motor-launch in the rapids at Niagara.
Consequently we had to wait until the high summer.

With hopes postponed to an indefinite future, another difficulty arose.
As it was found that the wind would not allow the sea-ice to form,
breaking up the floe as quickly as it appeared, the only remaining field
for manoeuvres was over the highlands to the south; under conditions
quite different from those for which it was suited. We knew that for
the first three miles there was a rise of some one thousand four hundred
feet, and in places the gradient was one in three and a half. I thought
the machine would negotiate this, but it was obviously unsafe to make
the venture without providing against a headlong rush downhill, if, for
any reason, power should fail.

Suggestions were not lacking, and after much consideration the following
device was adopted:

A hand rock-drill, somewhat over an inch in diameter, was turned up in
the lathe, cut with one-eighth-inch pitched, square threads and pointed
at the lower end. This actuated through an internal threaded brass bush
held in an iron standard; the latter being bolted to the after-end of
a runner over