The Elements of Natural Or Experimental Philosophy, Volumen3T. Cadell and W. Davies, 1803 |
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Página 111
... lens , they will be collected into a narrow space or focus , at a certain diftance from the lens . This focus has all the properties of the focus of reflected rays of heat ; which have been concifely mentioned above . In fimilar ...
... lens , they will be collected into a narrow space or focus , at a certain diftance from the lens . This focus has all the properties of the focus of reflected rays of heat ; which have been concifely mentioned above . In fimilar ...
Página 112
... lens of not more than an inch in diameter , the heat of the fun's rays may be collected fufficient- ly to fet fire to tinder , paper , gun - powder , wood , & c . but with large lenfes , or large concave mirrors , and a clear fun , the ...
... lens of not more than an inch in diameter , the heat of the fun's rays may be collected fufficient- ly to fet fire to tinder , paper , gun - powder , wood , & c . but with large lenfes , or large concave mirrors , and a clear fun , the ...
Página 113
... lens , the effect was prodigiously great . In about a minute's time it not only melted all forts of metallic ... lens in London , which coft a great deal of trouble , time , and expence , and which , I am forry to fay , is no longer in ...
... lens , the effect was prodigiously great . In about a minute's time it not only melted all forts of metallic ... lens in London , which coft a great deal of trouble , time , and expence , and which , I am forry to fay , is no longer in ...
Página 114
... moft convincing manner the reflection of heat , either quite independent of light , or accompanied with no great quite 114 Of the Production , & c . of Heat and Cold . Subftances fufed by Mr. Parker's lens, with their ...
... moft convincing manner the reflection of heat , either quite independent of light , or accompanied with no great quite 114 Of the Production , & c . of Heat and Cold . Subftances fufed by Mr. Parker's lens, with their ...
Página 182
... lens , at the diftance of about 10 feet , by which means an image well defined of the fun will be formed upon a screen placed at a proper distance from the lens ; but if a prifm be placed close to the lens , fo that the light , after ...
... lens , at the diftance of about 10 feet , by which means an image well defined of the fun will be formed upon a screen placed at a proper distance from the lens ; but if a prifm be placed close to the lens , fo that the light , after ...
Términos y frases comunes
alfo alſo angle angle of incidence appear atmoſphere attraction battery becauſe body cafe caloric colours concave conductor confiderable confifts convex convex lens courſe defcribed degree diſcharge diſtance divifions eafily electric fluid electrified electrometer equal eſpecially eye lens faid falt fame fcreen fecond feems feen fhall fhews fhock fide filk filver fingle firſt fituated fize fmall focal diftance focus fome fometimes fouth fpark fpecific ftate ftrong fubftances fuch fufficient furface glaffes glafs glaſs heat hole inches increaſe inftrument infulated iron itſelf lefs lenfes light magnet magnifying meaſure mercury metallic moft moſt muft muſt neceffary needle nitrous acid north pole obferved object object lens paffing perfons phial Philofophical piece plate poffeffed pofitive pole prefent prifm purpoſe quantity rays reflected reflector refraction reprefents ſmall ſtate teleſcope temperature thefe thermometer theſe thofe thoſe tricity tube uſed veffel whilft wire zinc
Pasajes populares
Página 287 - When the rising sun shines from that point whence its incident ray forms an angle of about 45° on the sea of Reggio, and the bright surface of the water in the bay is not disturbed either by the wind or...
Página 291 - ... let this mixture be rammed into a crucible of about an inch and a half in depth, till it be almoft full ; and let it be placed in...
Página 287 - ... palms, and nearly down to the sea, the observer will behold the scene of the same objects not only reflected from the surface of the sea, but likewise in the air, though not so distinct or well defined as the former objects from the sea.
Página 287 - Lastly, if the air be slightly hazy and opaque, and at the' same time dewy and adapted to form the Iris, then the abovementioned objects will appear only at the surface of the sea, as in the first case, but all vividly coloured or fringed witH red, green, blue, and other prismatic colours *. " As the day advances, the fairy scene gradually disappears.
Página 287 - Reggio, and the bright surface of the water in the bay is not disturbed either by the wind or the current, the spectator being placed on an eminence of the city, with his back to the sun, and his face to the sea ; on a sudden there appear in the water, as in a catoptric theatre, various multiplied objects, viz.
Página 418 - THE electric organs of the torpedo are placed on each side of the cranium and gills, reaching from thence to the semicircular cartilages of each great fin, and extending longitudinally from the anterior extremity of the animal to the transverse cartilage, which divides the thorax from the abdomen...
Página 203 - When the rings were examined by looking through the lenses in the opposite direction, the central spot appeared white, and, in other rings, red was opposite to blue, yellow to violet, and green to a compound of red and violet ; the colours formed by the transmitted and...
Página 140 - If two triangles have two angles of the one equal to two angles of the other, each to each, and one side equal to one side, viz.
Página 513 - ... the attraction of their matter. There is an attraction exerted between the overcharged extremity of one magnetic body and the undercharged extremity of the other, on account of the attraction between that fluid and the matter of the body ; but, to explain the repulsion which takes place between their undercharged extremities, we...
Página 278 - ... the distance of the small circle, and also of the parallel lines from your eye; divide then the distance of the former by that of the latter, and you will have the magnifying power of the telescope required.