THE CAMERA OBSCURA.

Star (Christchurch), Issue 3651, 23 December 1879, Page 2

THE CAMERA OBSCURA.

A curiously interesting fact was demonstrated yostorday, hy the exhibition of Mr Proctor's camera obsoura in tho Market square. This wns that, although, tho tttmosphcro was so heavily oharged with duet, tho pictures produoed wero iiovertheless very vivid, thus affording a romnrkablft comparison with the results which are ob-. t_io__l»._ London on a dull day. To thos» who have ever vUitod tho largo camera Q.Vsoura at tho Crystal Palaoo, tho oxhibitiop under notioe must afford overwhelming o?i---denoo of tho wondorful oloarnesi of the-at-mosphere in Now Zealand. Yesterday _. dust storm was well worth seeing in tho camera ob.oura, for the ploturo not only displayed otl-ots suoh as may bo soon, for example, in ! Rosa Bouheur's pioture, " The Homo Fair," , bnt tbe offoota had all tho added oharm of 1 motion. In point of fact, a, camera obscun. ' pioture may bo faithfully compared to an ' eiquifuMf fluiahod -wtw oolour pa\fttVP|»

the various details of which have in some mysterious manner become imbued with life and motion. Aa thero scorns to be an impression in the minds of many people that this highly interesting apparatus is of compiratively recent invention, it may be stated that the dato of its invention has been generally conceded to be about the year 1590. The apparatus consists of a dark room having a cupola-shaped roof. In an opening in the centre of tho roof is fitted a double convex lens of large size. Abovo the lens is a cubical box, one side of which opens outward. Within this box a sheet of silvered glass ia placed, in a diagonal position, so that any rays of light entering the side of the box aro reflected at right angles by means of tho silvered glass. They pasß through the double convex lens, and fall in a divergent form upon the white top of a table placed to receive the picture. Tho lens used by Mr P.octor haa a diameter of 12 inches, and -its focal length is 10 feet, tho pictures produced 'by its agercy having a diameter of 31 feet. Aa the cubical box containing tho reflecting glass can at will be presented to any point of the compass, it will readily bo understood .haft visitor to the camera obsenra have a somewhat extensive series of " living pictures " presented to .hem.