6 
NATURE NOTES. 
In the “summer country” more profound alterations have 
taken place. There the sheep have year after year cropped the 
sward bare, eating out in early summer, the season of blossom 
and seed, the sweet alpine plants and high hill annual grasses. 
Naturally, the turf has got more and more thin, and the shingle 
beneath less firmly fixed and more ready to break out. 
Finally comes a season, abnormally windy and dry ; the feed 
is barer than usual, the stock more restless. Their constant 
rambling wears away the thin layer of soil, a stone is displaced, 
the hole grows larger and larger as the fierce north-west gales 
blow out the dust and lighter pebbles. At length an incipient 
slip appears on the mountain side, and once begun, the touch of 
each sheep’s hoof, the breath of each gale, the brief torrent of 
each flood, adds to its size and length. The large quantity of 
gravel borne to the sea is of great moment to the whole of New 
Zealand, affecting as it does the height of the river beds, the 
coast line, and the amount of shingle drifted by the prevailing 
ocean currents into the various breakwaters of the colony. 
Landslips in the North Island are of an entirely different 
character. They occur from other causes than the shingle slips 
of the south, and in different ways. Even before the introduction 
of alien herbage there is evidence that landslips took place. 
Now, however, that the roots of the old vegetation — forest and 
fern — are gone, the frequency of slips is almost incredible. 
After heavy rain, indeed, looking from a distance at the hills, 
they appear to have been weeping clay. 
Broadly speaking, these earth avalanches may be classed 
in two groups — earth-slides and earth-slips; and again, speaking 
generally, it may be said that through their agency, the lands 
for one hundred and fifty miles along the east coast are 
moving slowly seaward, flattening out, as it were — the edges of 
the upper crust being swallowed by the sea or eaten away by 
the rivers. 
The four great factors in this movement are the extreme 
steepness of the hills, the nature of the rock — a soft clay easily 
disintegrated — the shallow roots of the new vegetation, and 
lastly, the almost tropical violence of the rains. My rain gauge 
registered on one occasion last year over seven inches in the 
twenty-four hours ; on another, in about ten hours four and a 
half inches fell. 
The earth-slides are movements of the larger character. 
They can be detected by trees slightly out of the natural angle, 
the bulging of fence lines, the bursting of gate fastenings, and, 
occasionally, the blotting out of a hill road. The slide usually 
narrows to a broadly ovoid shape at the top, where a crack of 
eight, ten, or twelve inches also attests the movement. An 
earth-slide does practically little damage, and in very many 
cases the movement does not seem to be regularly continuous. 
The earth slips, however, do great harm, for though the 
displacement of earth is less, the motion is much more violent. 
