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The economy of nature explained and illustrated on the principles of modern ...
Visualitzaciķ completa - 1798
The Economy of Nature Explained and Illustrated on the Principles ..., Volum 3
Visualitzaciķ completa - 1798
The Economy of Nature Explained and Illustrated on the Principles ..., Volum 2
Visualitzaciķ completa - 1796
acid angle angle of incidence apparent magnitude appear atmosphere attraction bodies boiling Book cafe caloric Chap cold colours combustion common concave concave lens conductor consequently converge convex convex lens degree of heat direction discoveries distance earth effect electric fluid electric matter electrified emitted equal evaporation experiments fame manner fire or heat flame focus force freezing glass greater ignited incident inflammable iron lens magnet matter of fire medium melted mercury metal mirror motion nature needle nitrous acid object observed Optics oxygen parallel particles pass phenomena phial philosophers phosphorus placed plate pole pound prism produced proportion quantity rays diverging rays of light reflecting surface reflector refraction refrangible retina saltpetre seen sensible heat sine solid specific gravity spherical spherical reflector substances supposed temperature theory thermometer tion tricity tube vapour velocity vessel
Pāgina 483 - ... majestic slowness ; at intervals we thought they were coming in a very few minutes to overwhelm us; and small quantities of sand did actually more than once reach us. Again they would retreat so as to be almost out of sight, their tops reaching to the very clouds.
Pāgina 483 - ... did actually more than once reach us. Again they would retreat so as to be almost out of sight, their tops reaching to the very clouds. There the tops often separated from the bodies ; and these, once disjoined, dispersed in the air, and did not appear more.
Pāgina 232 - P mn with that of the great one. Now, since in viewing a very remote object, we can scarcely see a point of it but what is at least as broad as the great mirror, we may consider the rays of each pencil, which flow from every point of the object, to be parallel to each other, and to cover the whole reflecting surface DUVF.
Pāgina 241 - The axis of the prism (that is, the line passing through the middle of the prism from one end of it to the other end parallel to the edge of the refracting angle) was in this and the following experiments perpendicular to the incident rays.
Pāgina 318 - C, standing on the floor, both appear to be electrized; for he, having only the middle quantity of electrical fire, receives a spark upon approaching B, who has an over quantity ; but gives one to A, who has an under quantity. If A and B approach to touch each other, the spark is stronger, because the difference between them is greater. After such touch there is no spark between either of them and C, because the electrical fire in all is reduced to the original equality.
Pāgina 241 - I let the refracted light fall perpendicularly upon a sheet of white paper at the opposite wall of the chamber, and observed the figure and dimensions of the solar image formed on the paper by that light. This image was oblong and not oval, but terminated with two rectilinear and parallel sides, and two semicircular ends. On its sides it was bounded pretty distinctly, but on its ends very confusedly and indistinctly, the light there decaying and vanishing by degrees.
Pāgina 10 - The idea of solidity we receive by our touch ; and it arises from the resistance which we find in body to the entrance of any other body into the place it possesses, till it has left it.
Pāgina 233 - B. in their way they form that extremity of the image at b. In like manner the rays E which come from the top of the object AB and fall parallel upon the great mirror at F, are thence reflected converging to its focus, where they form the lower extremity K of the inverted image...
Pāgina 341 - ... over a large tract of country, the lightning is seen to dart from one part of it to another, and often to illuminate its whole mass. When the cloud has acquired a sufficient extent, the lightning strikes between the cloud and the earth, in two opposite places; the path of the lightning lying through the whole body of the cloud and its branches. The longer this lightning continues, the...
Pāgina 491 - O A vapour, mist, or rain, descends with it, by which the path of it is marked with wet. The following is a description of one which happened a few years since at Leicester, about fifty miles from Boston, in New England : it happened in July, on a hot day, about four o'clock in the afternoon. A few clouds having gathered westward, and coming overhead, a sudden motion of their running together in a point being observed, immediately a spout of wind struck the...