Suche löschen...
The photographic news
- Bandzählung
- 6.1862
- Erscheinungsdatum
- 1862
- Sprache
- Englisch
- Signatur
- F 135
- Vorlage
- Hochschule für Grafik und Buchkunst Leipzig
- Digitalisat
- Hochschule für Grafik und Buchkunst Leipzig
- Digitalisat
- SLUB Dresden
- Lizenz-/Rechtehinweis
- Public Domain Mark 1.0
- URN
- urn:nbn:de:bsz:14-db-id1780948042-186200003
- PURL
- http://digital.slub-dresden.de/id1780948042-18620000
- OAI-Identifier
- oai:de:slub-dresden:db:id-1780948042-18620000
- Sammlungen
- Fotografie
- LDP: Historische Bestände der Hochschule für Grafik und Buchkunst Leipzig
- Bemerkung
- Seite 1-72 fehlen in der Vorlage. Vorlagebedingter Textverlust.
- Strukturtyp
- Band
- Parlamentsperiode
- -
- Wahlperiode
- -
- Bandzählung
- No. 203, Juny 25, 1862
- Digitalisat
- SLUB Dresden
- Strukturtyp
- Ausgabe
- Parlamentsperiode
- -
- Wahlperiode
- -
-
Zeitschrift
The photographic news
-
Band
Band 6.1862
-
- Ausgabe Ausgabe 73
- Ausgabe Ausgabe 85
- Ausgabe Ausgabe 97
- Ausgabe Ausgabe 109
- Ausgabe Ausgabe 121
- Ausgabe Ausgabe 133
- Ausgabe Ausgabe 145
- Ausgabe Ausgabe 157
- Ausgabe Ausgabe 169
- Ausgabe Ausgabe 181
- Ausgabe Ausgabe 193
- Ausgabe Ausgabe 205
- Ausgabe Ausgabe 217
- Ausgabe Ausgabe 229
- Ausgabe Ausgabe 241
- Ausgabe Ausgabe 253
- Ausgabe Ausgabe 265
- Ausgabe Ausgabe 277
- Ausgabe Ausgabe 289
- Ausgabe Ausgabe 301
- Ausgabe Ausgabe 313
- Ausgabe Ausgabe 325
- Ausgabe Ausgabe 337
- Ausgabe Ausgabe 349
- Ausgabe Ausgabe 361
- Ausgabe Ausgabe 373
- Ausgabe Ausgabe 385
- Ausgabe Ausgabe 397
- Ausgabe Ausgabe 409
- Ausgabe Ausgabe 421
- Ausgabe Ausgabe 433
- Ausgabe Ausgabe 445
- Ausgabe Ausgabe 457
- Ausgabe Ausgabe 469
- Ausgabe Ausgabe 481
- Ausgabe Ausgabe 493
- Ausgabe Ausgabe 505
- Ausgabe Ausgabe 517
- Ausgabe Ausgabe 529
- Ausgabe Ausgabe 541
- Ausgabe Ausgabe 553
- Ausgabe Ausgabe 565
- Ausgabe Ausgabe 577
- Ausgabe Ausgabe 589
- Ausgabe Ausgabe 601
- Ausgabe Ausgabe 613
- Register Index 619
-
Band
Band 6.1862
-
- Titel
- The photographic news
- Autor
- Links
- Downloads
- Einzelseite als Bild herunterladen (JPG)
-
Volltext Seite (XML)
THE PHOTOGRAPHIC NEWS. but if we double the velocity, we quadruple the heat. The heat developed, therefore, is exactly in proportion to the mechanical effect, or the mass of the body multiplied by the square of its velocity. In the experiments at Shoebury- ness it is a common thing to see a flash of light even in broad daylight when the ball strikes the target; and a rifle bullet developes an amount of heat on collision with the target, sufficient, if wholly concentrated in the lead, to raise its temperature 960°, or above its melting point. But we can convert heat back again into mechanical motion, and it has been found both by theory and experiment that an amount of heat equal to three-fifths of a degree Fahrenheit may be so expended as to raise a pound weight to the height of sixteen feet. The combustion of coal is a familiar instance of the production of mechanical effect by the expenditure of heat, and in this agent we possess an enor mous store of mechanical power. A pound weight of coal produces when burnt an amount of heat sufficient to raise a weight of one hundred pounds to a height of twenty miles above the earth’s surface, and conversely 100 lbs. falling from a height of twenty miles would generate, on striking against the earth an amount of heat equal to that developed by the combustion of a pound of coal. Wherever work is done by heat, heat disappears. A gun which fires a ball gets less heated than one which fires blank cartridge. Although the amount of heat developed by ordinary gravity appears insignificant in comparison to that developed by combustion, if we permit gravity to act throughout its entire range the disproportion ceases. Place a pound weight at such a distance from the earth that, the attraction of gravitation is barely sensible, and let it fall to the earth from this distance. It would reach the earth with a final velocity of 86,747 feet in a second, and on collision with the earth the body would generate twice the amount of heat evolved by the combustion its own weight of coal. Turning our attention from the earth to the sun, it has been found that the whole heat emitted by this orb in a minute is competent to boil 12,000 millions of cubic miles of ice cold water. Whence then, is the sun’s heat derived, and by what means is it maintained ? No combustion, with which we are acquainted, would be able to produce a temperature like this ; besides which, even sup posing the sun to be a solid globe of coal, it would burn itself out in 4,600 years. What agency can then produce the temperature and maintain the outlay ? We must seek for such a cause in the heat which is developed by mechanical motion. We have seen that a body falling from space into the earth, would generate twice the amount of heat evolved by the combustion of its own weight of coal. The maximum velocity with which such a body could strike the earth, is about seven miles in a second; whilst the maximum velo city with which itcouldstrike the sun. is 390miles in a second, when it would generate 10,000 times the heat of combustion of an equal weight of coal. It is almost certain that an infinite number of small bodies—planetary dust—exist in space ; the showers of meteoric stones so common on different parts of the earth’s surface, are part of these. The zodiacal light has been almost proved to consist of an assemblage of asteroids revolving round the sun; and moving as they do in a re sisting medium, they continually approach the sun and fall into it, producing the heat observed and constituting a source from which the annual loss of heat would be made good. The sun according to this hypothesis would be con tinually growing larger; but how much larger? Were our moon to fall into the sun it would develope an amount of heat sufficient to cover one or two years’ loss; and were our earth to fall into the sun a century’s loss would be made good. Still, our moon and our earth, if distributed over the surface of the sun, would utterly vanish from perception. Indeed the quantity of matter competent to produce the necessary effect would, during the range of history, produce no appreciable augmentation in the sun’s magnitude. The augmentation of the sun’s attractive force would be more appreciable. However this hypothesis may fare as a repre [July 25,1862. sentant of what is going on in nature, it certainly sho® how a sun might be formed and maintained by the apPlf cation of known thermo-dynamic principles. ■ • TANNIN AND HONEY PROCESS. After sensitizing the plate, attach the holder, and pout over the film a solution of one part honey to three parts water; let it flow three times round the surface, and then oft Place on a levelling stand, or level board, till next plate has been similarly treated, or until half a dozen or more have been thus prepared. Wash off the honey solution thoroughly under a tap, or with water from a jug. Stand to drain for one minute, then apply the tannin solution (5, 8, or 10 grains to the ounce), and dry. This plan of applying the diluted honey before washing oft' the free nitrate, is applicable to all dry processes. Caramel may answer as well. In this process, it is prefer able to mixing the honey with the tannin, as you get a cleaner plate, with less liability to stains, if the washing have been properly performed. In preparing dry plates, it is a matter of great importance to use soft water for washing them. Hard water coagulates the pyroxyline, and produces mottled films. Spring or pump water may often be soft enough, but where that is not the case, boiled and filtered rain water should be used. K. Uhe Jnternationul Cxhibition. BRITISH PHOTOGRAPHIC DEPARTMENT. The landscape photographs in the British Department is, as we have before intimated, out of all proportion the best in the Exhibition. It is not, however, illustrated by many novelties, the majority of the pictures having been exhibited before. The exquisite examples of Bedford, and Heath, and Mudd, have all before come under our notice. Wilson’s charming little views, 7 by 4 in., including a wide angle, by the triple lens, are novelties, and are universally admired. Here are Sidebotham’s “ Chepstow Castle’’ and “ Tintern Abbey,” by the collodio-albumen process, which we have noticed on a former occasion, and which we now think, notwithstanding the extensive collection in which they appear, are as fine pictures as ever have been produced by the art. Dixon Piper’s “ Old Curiosity Shop,” “ Lock Gates,” &c., have before been seen and admired ; a large in stantaneous picture entitled, “Early Morning,” is, we think, new ; it contains a magnificent study of clouds. The pho tographs of Sir A. K. Macdonald, Bart., we have already noticed at the Crystal Palace: all the specimens we have seen, both in the Exhibition and elsewhere, are among the finest examples of picturesque photography we have seen. Mr. Rouch exhibits a frame of the small landscapes of the same sort and style as those to which we have referred of Wilson’s. The subjects, which are all in the Isle of Wight, and include some instantaneous pictures, are well chosen and picturesque, and the photography delicate and brilliant, and the pictures altogether exceedingly good. Lieut.-Col. S. Wortley exhibits a series of views of Vesuvius in a state of eruption. These arc, in our estimation, amongst the most charming photographs in the Exhibition: each picture includes some view of the noble Bay of Naples, with Vesuvius belching forth smoke in volumes ; this, together with the exquisite natural clouds, are most perfectly rendered, indicating that the exposure has been instantaneous. There am some interesting views of the effects of the earthquake in the town of Torre del Greco. The majority of the pictures are on 12 by 10 plates, and were taken, we are informed, with the 8} by 6} triple lens. We regret that these prints were amongst the severe sufferers by the damp walls, ana are at present removed for the purpose of being replaced by fresh prints. Mr. Henry White exhibits a series ot very beautiful and well-selected views in North Wales, in whicl ,P i"tion BBntir ywBBeg V 6 ” Bmprac s" '”1 0 "tdated 3". Sig nVithot S^t "U anc pvro of >»h talme,re “.thep ahov S> t Bibitors art ■ nd yhos • '’SSUI Rlkethei C Vc d,l 3! Bye g"ew ' 3,0 "aslij 'K the phe ■ lions ft ! many 1 s exhibit f Campb k and sei ’ antiqui : the sub ! I, Nov : interest. pictures during Fenton contribu I collodio- I timber . % his Hi tributors i MEob I Wen £ I 0 lon, R We, F "hers. niscap bnotc . The I “playc mas
- Aktuelle Seite (TXT)
- METS Datei (XML)
- IIIF Manifest (JSON)