The Montgomery advertiser., 1903-09-20
SCIENTIFIC MISCELLANY
THE ALARM THERMoMETE-- SOUNDING FOR BROKEN
 BONES.
Atmospheric Acid-Light without Heat-Gas Bombs-Firemen's Danger from Electrified Water-An Engineer
 ing Model.

Among the instruments approved by the flre-fghting congress lately held fin London Is the electro ro-telethermometer oi Juan Villa Forms, of Corona, Spain. This Is simple automatic alarm, and consists essentially of mercury thermometer connected electrically with a bell and an indicating device. Platinum wires are sealed into the thermometer tube at in- | tervals of five degrees. The annunciator. which may be placed at any distance, is provided with a switch. and when the mercury rises to the point at which the | switch is set-say, to 120 degrees-the platinum wire is brought into the electric | circuit, causing the alarm bell to ring. A new test for fractures depend upon the difference between bone and soft tis- sue in the power of conducting sound. A stethoscope is placed over the bone at one side of the supposed fracture and a tuning fork is vibrated as near the bone as possible on the other side. If there Is no break the sound of the tuning fork should be transmitted very clearly through bone and stethoscope When there is still doubt. the test can be made conclusive by comparing the sound with that from the same bone on the oppo- site side of the body.
 
 tained by a Russian chemist-M. de Kowalski-by the old sparkling method of Cavendish. With a current of 5000 volts, having a frequency of 5000 or 10000 aI- formations per second, the best result from the air alone was about an ounce and a half of nitric acid per hour for each horsepower expended. Adding qgxy- gen to the air materially increased the yield.
 Measurements of gravity throughout Europe and Asia are expected to give a better idea of variations in weight and of the distribution of the bulk of the earth's crust.
 The N-rays of M. Blondlot, the French physicist. are proving one of the most interesting of the new forms of radiation, inasmuch as they seem to take us a step nearer to the solution of the problem of cold light. These rays penetrate black paper and many metals can be reflected and refracted by quartz lenses. and have no photographic action. but can be de- tected by their power of increasing the luminosity of small electric sparks or of a colorless blue flame. They have been found in the emissions of incandes- | cent gas-burners. M. Blondlots latest discovery is that these rays may increase | the DrlgntneSS or an lncanueScenl sup stance without adding to the heat and 1 the lighting up when the rays fell upon | a platinum wire at low redness gave no l rise in temperature although a very con- siderable increase in heat would be neces- sary to give the same effect.
 The novel observation has been made by NJ Berthelot. the distinguished French chemist, that cannon and other explosive discharges appear to project dense and cohesive masses of gas in addition to the smoke rings. This gaseous projectile bursts like a shell on meeting the necessary resistance. Some of the phenomena of the Mount Pelee eruption might be explained in this way, burning clouds having asphyxiated all living crea- lures on their route while persons not ex actly on the line escaped. M. Berthelot would apply the same theory to the tun- nel disaster in Paris. A gaseous projec- tile forced from the tunnel would explain | why persons were almost instantly suf- located 300 yards away from the actual | hre while persons much nearer were pass sd over unharmed.