Scientific.

Waikato Times, Volume XXVII, Issue 2239, 13 November 1886, Page 2 (Supplement)

Scientific.

Glonv^ampb Filled wrnr Hydrogen. -— Th'g Ulikrotcchnische Zeitcchvijfhi Atyxil, ;I886) Ba,y thst l.itwly the Brother Siemens haye 4 Seen ' manufacturing glow-lamps whose glares are filled with hydrogen. It. has been remarked before \ hut glowlamps in which (he inner glass wall had been rendered brown could bo cleaned by filling them with hydrogen aud then ex po*ipg both the carbon filitmonfc and >rliiB3 to a high temperature. These |a?Yips are said never to become brown at 1 , and to last, longer. They can be used with higher electromotive force*, and consequently under conditions considerably more favorable to economy, without diminishing their wear. It is thought that many evils that are found in the vaeuom glow-lamps now in use will disappear when the carbon filament is in an atmosphere of a gas exerting considerable pressure, but not acting chemically upon it. The Temprkatuhe of Lake Ltcmax. — It is remarkuble that the waters of Lake Leman, in Switzerland, have a comparatively high temperaturo at a depth of 200 to 390 metres. The temperature has, in fact, been found by various observer?, from Saussure downwards, to bo from 5 deg. to G^ deg. Centigrade: the latest observer being M. F. A. Forel, who by the help of a Negretti and Zambra doepnea thermomneter. found it to bo 5.3 deg. Centigrade this year. The temperature of these deep waters, however, vurioa from time to time. M. Forel, after a confederation of all the conjectured reasons for tho penetration of heat to the profound waters of the lake, arrives at the conclusion that the main cause is the mechanical mixture, produced by the prevaling winds, of the surface waters with chose below. The Earth Toward the Centre.— A remarkable example baa been presented at Posth, where the deepest artesian well tho world is that boring foi tho purpose of supplying tho public baths and other establishments with hot water. A depth of 3, 120 feet his iilre.uly boi?« reached, and it furnishes 176,000 jmUous daily, at a temperature of 7<> deg. Cent.— lsB deg. Fahr. The mnuicipHlity his recently voted a largo subvention, in order that the boring mly bo continued to a greater depth, not only to obtain a larger volume of water, but at a temperature of 80 dec Cent. — 176-» Fahr. It is huggested th.it it in thus within the bounds of probabilily that the time may come, when a brewer will obtiin his water Mipply from a well of sufficient depih to yield " liqu >rW' at the mashing temperature. " *