124 



SCIENTIFIC NE^VS. 



[Aug. 1st, lE 



GENERAL NOTES. 



Photographing Projectiles. — A photographer at Pesth 

 has succeeded in taking -photographs of projectiles, fired 

 from a Werendler gun, while having a velocity of 1,300 feet 

 per second. The projectiles appeared on the impressions 

 enveloped in a layer of air hyperbolic in form. 



Melting Gold at Low Temperature. — Gold will only 

 melt at a comparatively high temperature, as we all know, 

 but what is not generally known, the Jewellers' Jo?iriial says, 

 is that if two per cent, of silica be added to the gold, it can 

 be melted over the flame of a common candle. 



The Electric Light in the German Army. — It is said 

 that German regiments on a night march will in future be 

 preceded by a waggon carrying a powerful electric light, by 

 ■which, it is claimed, the road ahead can be seen^ and the 

 danger of surprise by an enemy considerably lessened. 



tr ectric Light for Omnibuses. — One of the omnibuses 

 of tl;e London Road Car Company, running between Liver- 

 pool Street and Victoria Station, has been supplied with an 

 " Eclipse " primary battery, which is used for lighting an 

 incandescent lamp. So far the trial is said to be very 

 satisfactory. 



Natural Gas. — While boring an artesian well at Lyons, 

 New York, natural gas was discovered quite unexpec- 

 tedly. In order to see down into the well a lighted 

 candle was lowered a few feet, when an explosion fol- 

 lowed, and a flame shot into the air. It is now proposed 

 to form companies for boring wells for natural gas in this 

 district. 



The Autographometer. — M. Floran de Villepigne, of 

 Paris, has devised an instrument which records automatically 

 the topography and difference of level of all places over 

 which it passes. It is carried about on a light vehicle, and 

 those who wish to use it have nothing to do but to haul it, 

 or have it hauled, over the ground of which they desire to 

 have a plan. 



Gold Alloy. — According to the Jewellers' Journal, a pretty 

 alloy, said to resemble gold exactly, can be made with six- 

 teen parts of copper, one of zinc, and seven of platinum. 

 The copper and platinum are first covered with borax, then 

 with powdered charcoal, and are afterwards melted, the 

 zinc being added. The alloy thus produced is exceedingly 

 malleable, and can be drawn into the finest wire, while it 

 is said not to tarnish. 



Artificial Ivory. — A substance resembling ivory, white 

 and very hard, can be made from good potatoes washed 

 in dilute sulphuric acid, and then boiled in the same solu- 

 tion until they become solid and dense. They are then 

 washed free from the acid and slowly dried. This ivory can 

 be dyed and turned and made useful in many ways. The 

 artificial ivory that will receive and retain a polish has not, 

 however, yet made its appearance. 



A Great Engineering Feat. — We learn from Iron that 

 a remarkable feat of engineering was recently performed in 

 America by the shifting en masse of an iron railway bridge, 

 weighing 1,600 tons a distance of 50 feet, at Holmesburg 

 Junction, on the Pennsylvania Railroad. The operation 

 was performed in less than twelve minutes, traffic was 

 uninterrupted, and in an hour after the change an express 

 train from New York to Philadelphia passed over the 

 structure. 



The Electric Light in Washington. — We learn from a 

 contemporary that a curious result of the electric light has 

 been observed in several of the public buildings in 



Washington, where it is used. It seems to constitute an 

 immense attraction for multitudes of minute insects, and as 

 a consequence spiders have increased enormously, so that 

 in many cases the architectural outlines of cornices and of 

 capitals of pillars have become obscured by the quantity of 

 spiders' webs overlying them. 



Liquid Fuel. — On the Pennsylvania Railroad a success- 

 ful trial has been made with liquid fuel applied to a loco- 

 motive. The fuel is the residue obtained from the oil 

 refineries, and was carried in barrels on the tender. 

 The furnace of the engine was specially lined with fire 

 brick, and the oil was fed into the furnace by means of 

 a steam jet, thus producing a spray and obtaining perfect 

 combustion. The apparatus is very similar to that used on 

 some of the steamers on the Caspian Sea. In making the 

 run of 116 miles, between eleven and twelve barrels of oil 

 were used, the average consumption of coal on the same run 

 being 3 tons 8 cwt. 



Aluminium — Silver Alloy. — Alloyed with a small per- 

 centage of silver, aluminium loses much of its malleabilitj',but 

 with five per cent, of silver it can be worked well, and takes 

 a more beautiful polish than the pure metal. With three 

 per cent, of silver it is very suitable for philosophical instru- 

 ments, being harder and whiter than the pure metal, and it is 

 not tarnished even by sulphuretted hydrogen. With small 

 amounts of silver it appears very suitable for scale beams, 

 and is now frequently used for this purpose. The alloy 

 containing five per cent, of silver has often been suggested 

 for coins of small denominations, as it is hard, bright, and 

 retains its lustre in handling. 



Submarine Telephony. — Professor Trowbridge's plan of 

 submarine telephony, in which speech was to be transmitted 

 between vessels at sea without the aid of any connecting 

 wire, has been abandoned as impracticable, but the system 

 upon which Mr. Edison has been experimenting in Florida 

 is more promising of good results. In this system the 

 telephone signals, by long and short explosive sounds 

 instead of by spoken words and communications, have been 

 successfully exchanged through the water between vessels 

 from three to four miles apart, with the prospect that the 

 working limit may be increased with improvement in the 

 apparatus. — Electrical Review. 



An Electric Trumpet. — We learn from La Nature that 

 an electric trumpet has been devised by M. Zigang. It 

 consists of a short brass tube mounted on wood, and con- 

 taining an electro-magnet whose ends face a vibrating plate, 

 on which is fixed a small piece of soft iron. Against this 

 plate-armature rests a regulating screw with a platinum 

 point, which serves for automatic interruption, by vibration 

 of the armature. With two Leclanche elements a musical 

 sound is obtained, which may be varied in pitch, intensity 

 and timbre by means of the screw. This instrument may 

 be usefully employed in signalling on ships, railways, tram- 

 ways, etc. ; it may also serve as a receiver for signals of 

 the Morse type. 



The Products of a Ton of Coal. — Besides gas, a ton 

 of gas coal will yield about 1,500 pounds of coke, 20 

 gallons of ammonia water, and 140 pounds of coal tar. 

 Destructive distillation of the coal tar gives 69 '6 pounds of 

 pitch, 17 pounds of creosote, 14 pounds of heavy oils, 9-5 

 pounds naptha yellow, 6'3 pounds of napthaline, 475 

 pounds of naphthol, 2"25 pounds of alizarine, 2-4 pounds of 

 solvent naptha, i'5 pound of phenol, i'2 pound of aurine, 

 I'l pound of aniline, 0-77 pound of toludine, 0*46 pound 

 of anthracine, and 0-9 pound of toluene. From the last- 

 named substance is obtained the new product known as 



