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Página 208 - All these things being considered, it seems probable to me that God in the beginning formed matter in solid, massy, hard, impenetrable, moveable particles, of such sizes and figures, and with such other properties and in such proportion to space as most conduced to the end for which he formed them; and that these primitive particles being solids are incomparably harder than any porous bodies compounded of them, even so very hard as never to wear or break in pieces, no ordinary power being able to...
Página 471 - The growth of coral appears to cease when the worm is no longer exposed to the washing of the sea. Thus, a reef rises in the form of a cauliflower, till its top has gained the level of the highest tides, above which the worm has no power to advance, and the reef of course no longer extends itself upwards.
Página 72 - ... may be completely restored by the use of hot water. For this purpose place the flowers in scalding •water, ' deep enough to cover about one-third of the length of the stem : by the time the water has become cold the flowers will have become erect and fresh : then cut off the coddled end of the stems, and put them into cold water.
Página 470 - ... invisible. These animals are of a great variety of shapes and sizes, and in such prodigious numbers, that, in a short time, the whole surface of the rock appears to be alive and in motion. The most common...
Página 394 - ... a quarter of an inch in length ; among them the Cancer fulgens was conspicuous. In another species (when put into the microscope by candle light), the luminous property was observed to be in the brain, which, when the animal was at rest, resembled a most brilliant amethyst about the size of a large pin's head, and from which, when it moved, darted flashes of a brilliant silvery light.
Página 470 - ... which are moved about with a rapid motion in all directions, probably to catch food. Others are so sluggish, that they may be mistaken for pieces of the rock ; and are generally of a dark colour, and from four to five inches long, and two or three round.
Página 470 - The examination of a coral reef during the different stages of one tide, is particularly interesting. When the tide has left it for some time it becomes dry, and appears to be a compact rock, exceedingly hard and ragged ; but as the...
Página 40 - The substance to be submitted to the action of the blowpipe must be placed on a piece of charcoal, or in a small spoon of platina, gold, or silver ; or, according to Saussure, a plate of cyanite may sometimes be used. Charcoal from the pine is to be preferred, which should be well ignited and dried that it may not crack. The sides, not the ends, of the fibres must be used ; otherwise the substance to be fused spreads about, and a round bead will not be formed.
Página 47 - Oxide of Lead melts, and is very quickly reduced, either without any addition, or when fused with microcosmic salt or borax. The glass not reduced is black. Oxide of Copper is not altered by the exterior flame, but becomes protoxide in the interior. With both microcosmic salt and borax it forms a yellow-green glass while hot, but which becomes blue-green as it cools.
Página 47 - ... by the minute metallic particles before they combine and form small globules. When a little soda is added to the glass formed with borax, the reduction is more easily effected, and the metal collects itself into one single globule. When this oxide contains iron, the glass retains its own colour while hot, but assumes that of the iron as it cools. Oxide of Tin...