196 THE ANTARCTIC MANUAL. 
flexible should be observed, both by watching them as they bend 
above the waves, and by experiments. The structure of such flexible 
ice sheets should be carefully observed, taking special note whether 
the ice be compact or porous, whether the ice-crystals in it are all 
parallel, or whether the sheet consists of a complex of irregularly 
arranged grains. 
Experiments should be made to test the weight required to bend 
a measured lath of such ice, and of the extent to which the lath will 
bend without breaking. 
(3) The formation of floe ice and its relation to the temperature 
should be noted, and the observations on its composition and that of 
the sea-water, which are described in the ‘Arctic Manual’ (pp. 638-9), 
should be continued. The changes, if any, in the floe ice as the 
winter proceeds should be observed; also, how far the presence or 
absence of salt in it depends on the temperature at which it is formed, 
and whether, as the spring approaches, the disintegration of the ice is 
aided by some kind of endosmosis of the sea-water. 
II. Coast Ick. 
In reference to the action of coast ice, data should be collected as 
to the height and distance to which ice floes travel up a beach from 
the pressure of grounding floes; notes should be made as to the effect 
of the ice masses on the rocks and beach material below, especially 
in regard to the production of striations on either of these, and the 
extent to which the latter may be incorporated in the lower part of 
the floe. Any contortions of the beach material should be sketched, 
with measurements of the dimensions of the contortions. 
III. Strucrure or THE Ick BARRIER. 
The origin of the Antarctic Ice Barrier, which extends Eastwards 
from Mts. Erebus and Terror, is still unsettled. As a contribution 
to the history of this ice, observations should be made as follows: 
(1) Its intimate structure, including the size, form and arrange- 
ment of the ice-grains. 
(2) The presence or absence of included layers of earth and stone; 
and, in the former case, their thickness and arrangement should be 
noted, their forms and the nature of the materials contained, their 
mode of weathering at the surface, the effect which they may produce 
on the movement of the ice, and their relation to shear planes; for it 
