Què opinen els usuaris - Escriviu una ressenya
No hem trobat cap ressenya als llocs habituals.
angle appears applied atmosphere attraction axis ball becomes bodies called cause changes charge cold colors column communication conducting conductor consequence consists constructed course cylinder diameter diminished direction discharge distance double earth effect elasticity electricity electrified employed equal excited exhibited experiments extremity fact feet figure fluid focus force give glass greater heat Hence inches incident increased insulated iron kind length lens less light machine magnet manner means medium metallic mirror motion nature nearly needle negative object observed opening opposite parallel passes phenomena piston plane plate poles portion positive pressure principle produced properties quantity rays receiver reflected refraction rendered respect seen separate side similar sometimes sound space spark steam string substance supposed surface temperature thunder tion tube turned valve various vibrations weight whole wind
Pàgina 41 - ... is equal to the weight of a column of water whose base is the section of the piston, and whose height is the distance of the level of the water in the barrel AC, above the level in the reservoir.
Pàgina 199 - That the best mode of communicating magnetism to a needle, appears to be by placing it in the magnetic meridian, joining the opposite poles of a pair of bar magnets (the magnets being in the same line) and laying the magnets so joined flat upon the needle with their poles upon its centre ; then having elevated the distant extremities of the magnets, so that they may form an angle of about two or three degrees with the needle, they...
Pàgina 90 - Nothing was ever written upon the subject of electricity, which was more generally read and admired in all parts of Europe than these Letters. There is hardly any European language into which they have not been translated; and, as if this were not sufficient to make them properly known, a translation of them has lately been made into Latin.
Pàgina 200 - That in the same plate of steel, of the size of a few square inches only, portions are found varying considerably in their capability of receiving magnetism, though not apparently differing in any other respect.
Pàgina 265 - ... very little of the violet. The yellow space, which has not been much absorbed, has increased in breadth. It occupies part of the space formerly covered by the orange on one side, and part of the space formerly covered by the green on the other. Hence it follows, that the blue glass has absorbed the red light, which, when mixed with the yellow light, constituted orange, and has absorbed also the blue light; which, when mixed with the yellow, constituted the part of the green space next to the...
Pàgina 322 - ... reflected from, the object. 2. Delicate observations should not be made when the fluid which lubricates the cornea is in a viscid state. 3. The best position for microscopical observations, is when the observer is lying horizontally on his back. This arises from the perfect stability of his head, and from the equality of the lubricating film of fluid which covers the cornea. The worst of all positions is that in which we look downward vertically.
Pàgina 172 - Each column is divided by horizontal partitions, placed over each other, at very small distances, and forming numerous interstices, which appear to contain a fluid. These partitions consist of a very thin membrane, considerably transparent. Their edges appear to be attached to one another, and the whole is attached by a fine cellular membrane to the inside of the columns. They are not totally...
Pàgina 37 - Hence the total pressure upon the side of a vessel containing water will be equal to the weight of a column of water whose base is equal to the area of...
Pàgina 152 - When a charged jar is placed under the receiver of an air pump, as the exhaustion proceeds, a luminous current flows over the edge of the jar, between the opposite sides, until the equilibrium is restored. Electric light exhibits a very beautiful appearance, as it passes or flows through the Torricellian Vacuum...
Pàgina 255 - F will be a bright disc surrounded and rendered indistinct by a broad halo of light growing fainter and fainter from F to G and H. In like manner, every object seen through such a lens, and every image formed by it, will be rendered confused and indistinct by spherical aberration.