POPULAR MISCELLANY. 



137 



gives the following account of the experi- 

 ment made to test the efficacy of this meth- 

 od of employing petroleum in place of 

 coal: "The little steamer Billy Collins was 

 selected by Mr. Campbell for the test. A 

 preliminary blaze of wood under the boiler 

 raised the small quantity of steam neces- 

 sary to start the burner into operation. 

 The oil-valve was opened ae trifle, the steam- 

 valve ditto. The petroleum trickled into 

 the feed-pipe, was caught up by the steam, 

 and both plunged into the depths of the 

 fire-box, a mass of many-tongued, roaring, 

 brilliant flame. As the pressure of steam 

 increased, this flame grew in fury and in- 

 tense heat. The needle of the steam-gauge 

 climbed rapidly up the dial, and in twenty 

 minutes the safety-valve blew off at 120 

 pounds pressure. ... To ocean-going 

 steamers this device must prove of extraor. 

 dinary interest. A tank of oil, situated at 

 a remote end of the ship, would hold fuel 

 BuflScient for a double trip, and supplant 

 the great coal-bunkers with their attend- 

 ant dirt." 



What ]Vordenskjdld has done.— A cur- 

 rent misapprehension of the work done by 

 Nordenskjold (pronounced Nordenshuld), 

 in his recent memorable voyage, is cor- 

 rected by the " Pall Mall Gazette." He 

 is supposed to have discovered the " North- 

 east Passage." He has discovered nothing, 

 not even the shore along which he sailed. 

 Every part of his route was known be- 

 fore, and the whole coast-line had been 

 laid down by the expeditions which, for 

 more than three hundred years, have pene- 

 trated from the east and west, or, descend- 

 ing the great Siberian rivets, have crept 

 along the European and Asiatic arctic shores 

 in boats or in dog-sleds. What Norden- 

 skjold has actually done is to have sailed, 

 in one continuous voyage and in one ship, 

 from the Atlantic to the Pacific, and to have 

 made en route a series of scientific collec- 

 tions and observations such as no other ex- 

 plorer in these seas — unless, perhaps, him- 

 self in former voyages — had been able to 

 carry away. Professor Nordenskjold is san- 

 guine that he has proved the feasibility of the 

 northeast passage for ships during most sea- 

 sons. This the " Pall Mall Gazette " pro- 

 nounces too hopeful a view, and assuredly a 



passage which requires over twelve months 

 for its accomplishment can hardly be called 

 " feasible " in any remunerative sense. But 

 one tiling is made clear by this voyage, name- 

 ly, that the great Siberian rivers drive the ice 

 off the coast during several of the late sum- 

 mer and autumn months, and that the Yeni- 

 sei and Obi may be reached during average 

 years. So confident is the Russian Govern- 

 ment that the products of their Asiatic em- 

 pire will find their way to European mar- 

 kets by way of the Siberian rivers and the 

 Arctic Sea, that they have already estab- 

 lished custom-houses at the entrance to the 

 Yenisei and the Obi. 



Eflfects of Tobacco on the Teeth. — Habit- 

 ual users of tobacco will draw some comfort 

 from observations made by the author of a 

 paper read before the Odontological Society 

 of London. This writer, Mr. Hepburn, says 

 that the direct action of nicotine on the 

 teeth is decidedly beneficial. The alkalini- 

 ty of the smoke must necessarily neutralize 

 any acid secretion which may be present in 

 the oral cavity, and the antiseptic property 

 of the nicotine tends to arrest putrefactive 

 changes in carious cavities. The author is 

 inclined to believe that the dark deposit on 

 the teeth of some habitual smokers is large- 

 ly composed of the carbon of tobacco-smoke. 

 This deposit takes place exactly in those 

 portions where caries is most likely to arise, 

 and on those surfaces of the teeth which 

 escape the ordinary cleansing action of the 

 brush. That tobacco is capable of allaying 

 to some extent the pain of toothache is, he 

 thinks, true — its effect being due not only to 

 its narcotizing power, but also to its direct 

 action on the exposed nerve ; and he is in- 

 clined to attribute the fact of the compara- 

 tively rare occurrence of toothache among 

 sailors in great measure to their habit of 

 chewing. 



Distribntion of Lnminons Power in the 

 Snn's Rays. — With the aid of a new spec- 

 trometer based on the optical principle that 

 a light becomes invisible when it is in pres- 

 ence of another light about sixty-four times 

 more brilliant, Professor J. W. Draper has 

 been enabled to prove that all the rays of the 

 sun's light possess the same luminous pow- 

 er. In the prismatic spectrum the luminous 



