576 



THE POPULAR SCIENCE MONTHLY.— SUPPLEMENT. 



is a water-tap with a revolving handle. " Our 

 Bruce " would turn the handle with ease and 

 help himself to a drink. It sometimes happened 

 that a hose-pipe would be attached to the tap ; 

 this would not cause him the least inconven- 

 ience; in such a case, after turning on the tap, 

 he would lift up the end of the hose-pipe with 

 his teeth and hold the end in his mouth until he 

 had satisfied his thirst. Many curious anecdotes . 

 could be told about our pet: how on one occa- 

 sion he picked up the end of the hose and wetted 

 one of the firemen who had offended him ; how, 

 at a fire, he would stand amid the greatest noise 

 and excitement, with showers of sparks falling 

 around him, and on his beautiful coat, only to be 

 shaken off; and at other times completely en- 

 veloped in smoke; but. there was no shying or 

 fretting under fire or smoke with " Our Bruce." 

 He seemed to know that he had brought those 

 who would fight that ruthless tyrant fire, and he 

 stood proud and confident that before long he 

 would return home with the victors, when, after 

 being refreshed and groomed, he would again be 

 ready, always first, for the next "turn-out." 



For nearly six years " Our Bruce " never 

 missed going with the first machine, at the end of 

 which time he was, in consequence of his fine ap- 

 pearance, and our desire to give him a less active 



duty in his old age, transferred from the fire- 

 engine to police-patrol duty. We did not alto- ' 

 gether lose our faithful animal's services, for one 

 of his duties was to attend fires with the mount- 

 ed police-sergeant (whose name was also Bruce) 

 to keep back the onlookers, which he most effect- 

 ually did for nearly two years, during which time 

 he was as great a favorite with the policemen, 

 rarely leaving a police-station without an apple, 

 a piece of bread, or some mark of affection. 



On the 7th of June "Our Bruce" fell sick; 

 the veterinary surgeon was sent for, who pro- 

 nounced him suffering from inflammation of the 

 bowels. The usual remedies were applied, and 

 everything was done to relieve his pain and make 

 him comfortable, but to no avail. For three days 

 afterward he was never left for a moment, night 

 nor day, and at the end of the third day he drew 

 his last breath, surrounded by those who loved 

 him well, and who had been taken by him to the 

 scene of many a hard fight. A post-mortem ex- 

 amination was held the following morning to 

 ascertain the cause of death. A stone (calculus) 

 six inches in diameter, weighing five pounds 

 eleven ounces, was taken from his bowels. This 

 was, no doubt, the principal cause of the disease 

 which led to the death of the fire-horse, "Our 

 Bruce." — Science- Gossip. 



BEIEF NOTES. 



Darkness of Lamp Caverns. — As every one 

 who has ever explored a cavern knows, the dark- 

 ness of subterranean cavities is intense, and a 

 torch or lamp serves to illumine only a very lim- 

 ited area. The cause of this is explained by a 

 writer in Nature, Salvador Calderon, who points 

 out how the ever-wet walls, floor, and roof, of a 

 cavern serve to retain the particles floating in the 

 air. This moisture " performs the same function 

 that the glycerine does which varnishes the sides 

 of the crystal box by means of which Prof. Tyn- 

 dall obtains an optical vacuum, the light diffusing 

 itself imperfectly, from the want of those particles 

 which act as reflecting bodies. I have had occa- 

 sion," he adds, "to verify my supposition by scat- 

 tering around the torch very fine dust of different 

 substances. The brightness diffused itself regu- 

 larly all the time that the dust maintained itself in 

 the required state of closeness and fluctuation, and 

 vanished again slowly as the dust spread or de- 

 posited itself." 



Allolropic Copper. — A very interesting allo- 



tropic modification of copper is obtained by Sekut- 

 zenberger by the electrolysis of a ten per cent, so- 

 lution of copper acetate. During the electrolysis 

 the surface of the negative electrode which faces 

 the positive copper electrode becomes covered with 

 a layer of the allotropic copper, while the other side 

 of the electrode is covered with a deposit of ordi- 

 nary copper. The allotropic modification forms 

 glittering metallic scales, with roughened surfaces 

 on the side next the solution : should the electroly- 

 sis be carried on long enough, beautiful tree-like 

 forms are deposited on the edge of the negative 

 electrode, which gradually ramify over to the posi- 

 tive electrode. The allotropic copper is less red 

 than the ordinary variety, possesses surfaces with- 

 out malleability, and can be reduced to an ex- 

 tremely fine powder. Its density, 8 to 8.2, is high- 

 er than that of ordinary copper, which is about 

 6.9. It oxidizes rapidly in the air, becoming at 

 once 'iridescent, and finally of an indigo-blue col- 

 or ; when exposed to the air as a powder, it be- 

 comes black, changing finally into the oxide. 



