August i, 1885 .] The. Australasian Scientific Magazine. 13 
country may be barren, wooded or cultivated ; it may be arid or watered 
by streams, it may contain many lakes, etc. The undulations may be 
abrupt, or may be gently swelling, and this may be in a great measure 
owing to the nature of the subsoil, whether it consists of gravel, or sand, or 
rock; but a country of this description is easily described. A hilly country, 
on the other hand, is more complicated. Not only is the term vague or 
uncertain, but other features have to be considered in reference to it. 
Neither hills nor mountains can exist without valleys, and these must also 
be considered and described at the same time. Then again, the hills 
themselves may be of various forms and characters ; do they extend in 
long parallel chains or ranges, or are they detached and isolated? Do 
these ranges of hills radiate or converge ? Do they rise abruptly or 
gradually from the low country ? How are they wooded? What do the 
rocks which constitute their nucleus consist of? If possible, it is desirable to 
ascertain their height, which, in the absence of complicated instruments and 
barometers, may be obtained approximative^ by marking the exact point at 
which pure fresh water boils. It is an undoubted fact that water, when heated 
in an open vessel, boils at a lower temperature in proportion as we ascend to a 
higher elevation above the level of the sea. It is hardly necessary to 
observe that the same accuracy cannot be obtained as with the barometer, 
but much may be done by the help of well-graduated thermometers. 
2. Mountain Ranges. — The most important features in the configura- 
tion of a country are the mountain ranges by which it is traversed. The 
exact point of distinction between a hill and a mountain is difficult to 
describe ; in some cases it will be purely comparative, in others it will 
depend on the general character of the country, and in some it will be 
arbitrary. But In all cases it will be desirable to endeavour to ascertain 
the height of the principal points, the direction of the main ranges or 
chains, and whether they are parallel or not. The ridges also may be 
serrated , or smooth and even, and the summits themselves will be either 
pointed, or dome-shaped, or flat. Is the mountain insulated or not ? and 
if so, is it conical and sloping on all sides to the surrounding plains ; or 
does it consist of a detached ridge ? Many of these points will be found 
to depend on the geological formation of the country ; and, as we have 
observed, this branch of our subject is very closely connected with that 
science. It is also desirable to ascertain how far the mountain tops are 
covered with perpetual snow, and how far down their sides snow lies during 
the whole or any considerable portion of the year. Is there any marked 
difference in the slope on one side or on the other? Does vegetation 
abound more on one side than on the other? i.e., in New Zealand 
nearly all the mountain ranges, which extend from north to south (and this 
is their principal direction), are covered on their southern flanks with vegeta- 
tion, while on the northern flanks, exposed to the rays of the sun, are 
almost void of vegetation, barren, and generally rocky. This superior 
vegetation on the southern flanks is probably owing to the less rapid 
melting of the snows or drying up of the rain than those on the northern 
flanks. It may also sometimes be owing to the fogs and vapours driven up 
by the sea breezes, condensed on coming in contact with a colder body, 
or attracted and retained by the hills themselves. Nor can we complete 
our information respecting a mountain chain, unless we know the length to 
which it extends, and the breadth of country' which it covers. 
Valleys are a necessary complement to mountain masses, and there are 
many peculiarities connected with them well deserving of observation. 
Are the sides precipitous or sloping ? Are they wide or narrow? well watered 
