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Mountain : HillA mountain is a landform that extends above the surrounding terrain[?] in a limited area. A mountain is generally much higher and steeper than a hill, but there is considerable overlap, and usage often depends on local custom; see also Dune. A mountain is usually produced by the movement of lithospheric plates, either orogenic movement[?] or epeirogenic movement[?]. The compressional forces, isostatic uplift and intrusion of igneous matter forces surface rock upwards, creating a landform higher than the surrounding features. The height of the feature makes it either a hill or, if higher and steeper, a mountain. The absolute heights of features termed mountains and hills vary greatly according to an area's topography. The major mountains tend to occur in long linear arcs, indicating tectonic plate boundaries and activity. Mountain creation tends to occur in discrete periods, referred to as orogenies (orogeny). Two types of mountain are formed depending on how the rock reacts to the tectonic forces - block mountains or fold mountains. Some isolated mountains were produced by volcanoes, including many apparently small islands that reach a great height above the ocean floor. Block mountains are created when large areas are widely broken up by faults creating large vertical displacements. The uplifted blocks are block mountains or horsts[?]. The intervening dropped blocks are termed graben[?], these can be small or form extensive rift valley systems. This form of landscape can be seen in East Africa, the Vosges, the Basin and Range province of Western North America and the Rhine valley. Where rock doesn't fault it folds, either symmetrically or asymmetrically. The upfolds are anticlines and the downfolds are synclines, in asymmetric folding there may also be recumbent and overturned folds. The Jura mountains are an example of folding. Over time erosion can bring about an inversion of relief, the soft upthrust rock is worn away so the anticlines are actually lower than the tougher rock of the synclines. The highest mountain on Earth is Mount Everest, set in the world's most significant mountain range, the Himalayas. Another contender for this title is Mauna Loa, which stands taller than Mount Everest when measured from its base on the ocean floor but not in terms of summit altitude. The tallest mountain in the solar system is Olympus Mons, located on Mars. Some mountains are very difficult to climb, and offer spectacular views. Some people therefore enjoy the sport of mountaineering. Mountains are also the site for the sport of downhill skiing. A popular form of playing at the beach is making a sand "mountain". See also: List of mountains, Mountain range, List of mountain ranges Pardon me. I could not tell.html">tell.html">tell you them off-hand.html">hand at a moment's
produce them. I cannot tell how anxious I am/am.html">am to hear your statement.
Glauc. No, I assure you, I have not got them even on paper yet.
Soc. Well then, we will defer tending advice.html">advice.html">advice.html">advice on the topic of peace or
to the magnitude of the questions, in these early days of your
that you have studied the defences of the country.html">country, at all events, and
how many are not; you can tell us which garrisons are strong enough.html">enough
your advice in favour of increasing the serviceable outposts and
"Revenues."
Glauc. Yes, sweep them all away, that's my advice; for any good that
property of the rural districts is simply pilfered.
But suppose you sweep away the outposts (he asked), may.html">may not something
free to any ruffian who likes? . . . But may I ask is this judgment
the defences? or how do you know that they are all maintained as you
shall we defer giving advice on the matter.html">matter? (It will be time enough
have not visited them in person, so as to be able to say why they are
matter.
Well, no; I have never been there myself (he answered).
Soc. No, Heaven help us! an unhealthy district by all accounts; so
an excuse ready to hand.
I see you are making fun of me (Glaucon answered).
Soc. Well, but here is a point, I am sure, which you have not
us. For how long a time could the corn supplies from the country
so that the city may not run short of this prime necessary, before. All is still licensed under the GNU FDL.
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