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A manual of natural philosophy, by J.L. Comstock and R.D. Hoblyn
John Lee COMSTOCK
Vista completa - 1846
A Manual of Natural Philosophy, by J.L. Comstock and R.D. Hoblyn
Richard Dennis Hoblyn,John Lee Comstock
Sin vista previa disponible - 2016
air-pump angle appear atmosphere attraction axis ball boiling bulk called centre of gravity centrifugal force circle cold colours concave concave mirror condensation consequently convex convex lens convex mirror cylinder degrees diameter direction distance earth ecliptic effect elastic electricity engine equal equator Explain Fig falling body feet fluid force fulcrum glass greater heat Hence hydrometer illustrated inches inclined plane increased instrument latent heat length lens lever liquid machine magnet mercury metals miles mirror moon motion move object orbit orifice particles pass pendulum perpendicular pipe piston placed poles pounds pressure principle produced proportion pulley pump quantity of matter raised rays of light reflected refracted respect retina revolution revolve rise rope round screw seen side solid space specific gravity stars steam substances Suppose surface temperature thermometer thrown tion tube valve velocity vessel vibrations visual angle weight wheel wire
Página 303 - Mars a rather large pin's head, on a circle of 654 feet; Juno, Ceres, Vesta, and Pallas, grains of sand, in orbits of from...
Página 317 - Different opinions have been advanced by astronomers respecting the cause of these appearances. By some, they have been regarded as clouds, or as openings in the atmosphere of the planet, while others imagine that they are the marks of great natural changes, or revolutions, which are perpetually agitating the surface of that planet. It is, however, most probable, that these appearances are produced by the agency of some cause, of which we, on this little earth, must always be entirely ignorant.
Página 190 - ... came to prepare with all haste for a storm. The barometer had begun to fall with appalling rapidity. As yet, the oldest sailors had not perceived even a threatening in the sky, and were surprised at the extent and hurry of the preparations: but the required measures were not completed, when a more awful hurricane burst upon them than the most experienced had ever braved. Nothing could withstand it; the sails already furled and closely bound to the yards, were riven away in tatters; even the bare...
Página 202 - I considered how to produce rotative motions from them in the best manner ; and amongst various schemes which were subjected to trial, or which passed through my mind, none appeared so likely to answer the purpose as the application of the crank in the manner of the common turning-lathe (an invention of great merit, of which the humble inventor, and even its era, are unknown).
Página 459 - A sphere is a solid bounded by a curved surface, every point of which is equally distant from a point within called the center.
Página 243 - The transparent body through which the light passes is called the medium, and it is found in all cases, that where a ray of light passes obliquely from one medium into another of a different density, it is refracted, or turned out of its former course.
Página 471 - SKY, the blue expanse of air and atmosphere. The azure colour of the sky is attributed, by Sir Isaac Newton, to vapours beginning to condense there, and which have got consistence enough to reflect the most flexible rays. SNOW, a well known substance, formed by the freezing of the vapours in the atmosphere. It differs from hail and hoarfrost, in being as it were crystallized, which they are not. SOLID, in...
Página 310 - It is a fact, not a little interesting to Englishmen, and, combined with our insular station in that great highway of nations, the Atlantic, not a little explanatory of our commercial eminence, that London occupies nearly the center of the terrestrial hemisphere.
Página 202 - ... ascent,) I proposed to employ two engines, acting upon two cranks fixed on the same axis, at an angle of 120° to one another, and a weight placed upon the circumference of the flywheel at the same angle to each of the cranks, by which means the motion might be rendered nearly equal, and only a very light fly-wheel would be requisite.
Página 301 - ... who could foretell eclipses, and who discovered the precession of the equinoxes, still believed that the earth was at rest in the centre of the universe, and that all the hosts of heaven performed a daily revolution about it as a centre. It usually happens in scientific progress, that when a great fact is at length discovered, it approves itself at once to all competent judges. It furnishes a solution to so many problems, and harmonizes...