254 



THE POPULAR SCIENCE MONTHLY. 



MAGNETIC VARIATIONS. 



The last word about solar influence is 

 uttered by Carl Horustein, of Prague, who, 

 summing up the results of an immense num- 

 ber of observations, says that the variations 

 of each of the three elements of terrestrial 

 magnetic force, declination, inclination, and 

 horizontal intensity, have a period of about 

 26 days. This periodicity can hardly be 

 explained, except by the influence of the 

 sun. 



COLD IN GERMINATION. 



The cold of winter is said by M. Du- 

 claux, of the Paris Academy of Sciences, to 

 be necessary for the germination of certain 

 vegetable grains, and for hatching the eggs 

 of the silk-worm. His researches in this 

 matter he proposes to continue and to ex- 

 tend, so that the effects of cold may be as- 

 certained to the greatest possible degree of 

 exactitude. 



NOTES. 



A remarkable case of reproduction of 

 the elbow-joint after resection is given by the 

 British Medical Journal. The subject was 

 a weakly girl, aged 13, whose elbow had be- 

 come fixed in a faulty position, after inflam- 

 mation. On account of this, and of disease 

 of the bone, resection or removal of the 

 joint was performed. The piece of bone re- 

 moved was one and a third inch long in 

 front, and two and a half inches behind ; 

 the articular portions of the bones of both 

 arm and forearm being thus taken away. 

 The child recovered, with power of moving 

 the elbow between the angles of 60 and 113 

 degrees ; rotation, however, was impossible. 

 Two and a half years after the operation, 

 the child died, and, on examination, a new 

 elbow-joint was found, having its articular 

 surfaces covered with cartilage, and provided 

 with a synovial membrane. 



TnE Engineer says that the oxyhydric 

 light has not proved a success in Paris, and 

 it has been discontinued in the public lamps 

 on the Boulevard des Italiens. It is not 

 generally known that a carburating appara- 

 tus is always employed in conjunction with 

 oxygen, which adds to the complication of 

 the appai itus as well as the cost of the light. 

 There are but few, remarks Le Gaz, who 

 will consent to have installed in their houses 

 two meters, two regulators, a carburator, and 

 two distinct systems of pipes. For this rea- 

 son alone the system was certain to fail, 



even if the alleged economy were proved 

 which has never been the case. 



A simple mode of distinguishing with 

 certainty between apparent and real death 

 is given by Dr. Ars-Drouet, of the Paris 

 Academy of Medicine. It consists in fast- 

 ening a bandage, handkerchief, or cravat, 

 etc., around the forearm, just below the 

 elbow, or around the leg below the knee. 

 If the patient still lives, the subcutaneous 

 veins become inflated, swollen, and bluish 

 under the skin ; but, if life is extinct, there 

 will be no change iu the appearance of these 

 veins. 



From a statement made by Dr. Giinther, 

 in the January number of the Magazine of 

 Natural History, it would appeal' that the 

 national collection which in the year 1858 

 contained 480 species of snakes, represented 

 by 3,990 examples, possesses now 920 spe- 

 cies, represented by 5,500 examples. The 

 number of typical specimens is 366, the to- 

 tal number of species of snakes known at 

 present being calculated at about 1,100. 



The perfect fossil skeleton of a man has 

 just been discovered in a cavern near Meu- 

 don, France, by Dr. Riviere, who sends a 

 communication on the subject to the French 

 Geological Society. The skeleton was in an 

 inclined position, and in the attitude of re- 

 pose : the legs were partially bent, and the 

 one rested on the other. A necklace made 

 of shells and perforated teeth was found 

 upon it. 



Experiments with petroleum as a fuel in 

 the puddling-furnace are said to have been 

 attended with great success in France. The 

 experiments were made under many varying 

 conditions, and were conducted by practical 

 and reliable men. It is asserted that, for 

 convenience, efficiency, and, above all, for 

 the superior quality of iron produced, there 

 is nothing that equals petroleum in this 

 manufacture. 



In a paper react before the Iron and 

 Steel Institute of England, Mr. J. Head 

 states that, while there is as much heating- 

 power in a pound of average coal as is 

 necessary to procuce IV pounds of puddled 

 bar-iron, there are few furnaces where more 

 than one pound of iron is brought out to 

 one pound of coal consumed. 



If a sailing-ship be provided with a 

 screw - propeller, the latter will revolve 

 when the ship makes way ; and it is pro- 

 posed to apply the power thus obtained to 

 operating a magnetic apparatus, which would 

 furnish a far brighter signal-light than any 

 oil-lamp. 



