contain no aqueous moisture and are not watery, but in which heat and earth preponderate, like honey and must (for these are in a sort of state of effervescence), and those which do possess some water but have a preponderance of air, like oil and quicksilver, and all viscous substances such as pitch and birdlime.
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Those bodies admit of softening which are not (like ice) made up of water, but in which earth predominates. All their moisture must not have left them (as in the case of natron and salt), nor must the relation of dry to moist in them be incongruous (as in the case of pottery). They must be tractile Ralph Lauren Långärmade skjortor (without admitting water) or malleable (without consisting of water), and the agent in softening them is fire. Such are iron and horn.
Both of bodies that can melt and of bodies that cannot, some do and some do not admit of softening in water. Copper, for instance, which can be melted, cannot be softened in water, whereas wool and earth can be softened in water, for they can be soaked. Ralph Lauren Vest Sweaters (It is true that though copper can be melted the agent in its case is not water, but some of the bodies that can be melted by water too such as natron and salt cannot be softened in water: for nothing is said to be so affected unless the water soaks into it and makes it softer.) Some things, on the other hand, such as wool and grain, can be softened Piumini Uomo Moncler Giacche by water though they cannot be melted. Any body that is to be softened by water must be of earth and must have its pores larger than the particles of water, and the pores themselves must be able to resist the action of water, whereas bodies that can be ‘melted’ by water must have pores throughout.
(Why is it that earth is both ‘melted’ and softened by moisture, while natron is ‘melted’ but not softened? Because natron is pervaded throughout by pores so that the parts are immediately divided by the water, but earth has also pores which do not connect and is therefore differently affected according as the water enters by one or the other set of pores.)
Some bodies can be bent or straightened, like the reed or the withy, some cannot, like pottery and stone. Those bodies are apt to be bent and straightened which can change from being curved to being straight and from being straight to being curved, and bending and straightening consist in the change or motion to the straight or to a curve, for a thing is said to be in process of being bent whether it is being made to assume a Kurtki Peuterey Męskie convex or a concave shape. So bending is defined as motion to the convex or the concave without a change of length. For if we added ‘or to the Belstaff Brian Długo Kurtki straight’, we should have a thing bent and straight at once, and it is impossible for that which is straight to be bent. And if all bending is a bending back Eibar Pas Cher or a bending down, the former being a change to the convex, the latter to the concave, a motion that leads to the straight cannot be called bending, but bending and straightening are two different things. Moncler kurtki Kobiety 2014 These, then, are the things that can, and those that cannot be bent, and be straightened.
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