POPULAR MISCELLANY 



427 



M. Pasteur employed in 1S5Y, and which 

 enables him to obtain microscopic organ- 

 isms in a state of purity the only means 

 of arriving at certain results. An infinitely 

 small drop of the blood from a case of ma- 

 lignant pustule is taken, and it is sown in 

 the cultivating fluid constituted by a froth 

 of beer-yeast; a little drop of this fluid is 

 taken again, and sown in a new medium of 

 the same kind, and so on. Thus the media 

 of culture may be multiplied indefinitely to 

 a certain extent during years by the aid of 

 a single droplet of blood taken originally 

 from the case, and one may have always a 

 liquid the inoculation of which in certain 

 animals, such as the sheep or Guinea-pig, 

 reproduces in those animals malignant pus- 

 tula?. If this fluid is filtered through a 

 plaster filter, nothing results from the in- 

 oculation of the fluid parts which have trav- 

 ersed the filter, but, if the figurate elements 

 which remain on the filter be inoculated, all 

 conditions of the pustular disease are pro- 

 duced. It is the same with the cholera of 

 fowls, and perhaps with puerperal septicae- 

 mia." 



Marey on Electrical Fishes. Of a com- 

 munication from Professor Marey to the 

 Paris Academy of Sciences on electrical 

 fishes, a brief summary is given in the 

 " Revue Scientifique," from which we learn 

 that the author employed a telephone in 

 studying the nature of the electrical dis- 

 charge of the gymnotus, and the torpedo. 

 Physiologists long ago pointed out certain 

 analogies of innervation, chemical composi- 

 tion, and structure observable between mus- 

 cles and the electrical apparatus of these 

 animals. It remained to be discovered 

 whether these analogies also exist in the 

 functionment of the two organs. Marey's 

 experiments go to show that the electrical 

 and the muscular functions are in reality 

 homologous, and that they are destined to 

 explain each other. The author also inves- 

 tigated the question whether in those spe- 

 cies of fishes which give the electrical dis- 

 charge there is to be observed a multiplicity 

 of electrical discharges just as a multiplici- 

 ty of shocks are to be observed in muscular 

 action. The experiments yielded affirmative 

 results. They were made according to the 

 graphic method, as also with the aid of the 



telephone, the latter instrument being spe- 

 cially adapted for this kind of investiga- 

 tion, inasmuch as it gives a sound when it 

 is traversed by successive currents of suffi- 

 cient frequency. 



Variable Stars. In directing attention 

 to a certain remarkable star, the "Acad- 

 emy " relates an intei'esting passage of his- 

 tory connected with it. A Jesuit Professor 

 at Ingolstadt, Christopher Scheiner, was one 

 of the first observers of sun-spots, having 

 noticed them in March, 1611. In accord- 

 ance with the rule of his order, he com- 

 municated his discovery to Budaeus, his 

 superior, who, being a disciple of Aristotle, 

 would not accept the observation as correct, 

 inasmuch as no such thing was to be found 

 mentioned in the works of " the Philoso- 

 pher." When Scheiner had satisfied him- 

 self that he had made a true observation, 

 he was permitted to publish the fact, but 

 anonymously. Accordingly, he addressed 

 several letters to Welser, a wealthy Augs- 

 burg patrician, and a great patron of learned 

 men ; these were printed, and copies sent 

 to Galilei and other astronomers. In the 

 autumn of 1612 Welser published three 

 more letters by Scheiner, under the title 

 "De Maculis solaribus," etc., the second 

 of which, dated April 14, 1612, records ob- 

 servations of Jupiter and his satellites from 

 March 29th to April 8th, among them some 

 observations to which Professor Winnecke, 

 of Strasburg, has lately drawn attention. 

 In order to understand why observations 

 of the satellites of Jupiter were mixed up 

 with those of sun-spots, one must bear in 

 mind that at that time Scheiner still as- 

 sumed the spots to be merely satellites of 

 the sun, and thus avoided inconvenient 

 questions respecting the purity of the sun's 

 light, which the Aristotelians would not give 

 up. While observing Jupiter's satellites he 

 saw something which offered, as he fancied, 

 a new analogy in support of his opinion ; 

 for on March 30, 1612, he remarked in the 

 field of the telescope, besides the four sat- 

 ellites, a fifth star, which he had not noted 

 the previous night. This star decreased in , 

 brightness from night to night, and had, on 

 April 9th, already passed the limit of visibili- 

 ty. Scheiner, moreover, thought he had re- 

 marked a small amount of motion, and he 



