Natural History, S3t 



very interesting microscopical observations on the distribution of 

 the nerves in the muscular fibres, and on the forms which these 

 latter assume durinc^ their contractions. They placed a thin piece 

 of muscle retaining its nerves under the microscope, and made it 

 contract by means of galvanism. The fibres contracted by bending 

 in a zigzag manner, and the last nervous filaments were seen to 

 proceed parallel to each other, from the branch giving origin to 

 them, to be inserted precisely at the points where the fibres form 

 their angles. — Jameson's Jour nal, 1827, p. 200. 



2. Disease of Silk Worms and its cure. — In the southern parts of 

 France, where silk worms are raised, it is very common to observe 

 the insects attacked by a disease called the jaundice, in consequence 

 of the colour acquired by them. Very careful examination is con- 

 tinually made for the discovery of such worms as may be attacked 

 by it, that they may be removed, lest the disease, being contagious, 

 should spread to the others. 



The Abbe Eysseric of Carpentras had recourse to a remedy in 

 these cases, which, though apparently dangerous, had been war- 

 ranted by the success of twenty years. He used to powder his 

 worms over with quick lime by means of a silk sieve ; he then gave 

 them mulberry leaves moistened with a few drops of wine, and the 

 insects instantly set about devouring the leaves with an eagerness 

 which they did not usually show. Not one of the hurdles upon 

 which he raised his worms appeared infected with the jaundice. 

 It was at first supposed, that the cocoons of silk were injured by 

 this process ; this, however, is not the case, and his method of prac- 

 tice is now adopted generally in the department of Vaucluse.— 

 Bull, Univ, D. viii. 360. 



3. Temperature below the Earth's Surface. — Mr. Fox, in an ad- 

 ditional paper relative to the temperature of the interior of the earth, 

 as indicated by the temperature of the waters issuing from the 

 bottoms of mines, states, upon the authority of a friend, in the firm 

 of Barclay, Perkins, and Co., that the water in a well in their 

 premises, in Southwark, 140 feet deep, is invariably at the tempera- 

 ture of 54°, which is 4°.5 above the mean climate of London, ac- 

 cording to Howard, who calls it 49°.5. 



From experiments made upon the mean temperature for a whole 

 year, at the following places, in the mining districts, namely,— 



Huel Gorland 48.99 



Dolcoath 49.94 



Falmouth 50.67 



Mean 49.65 



it would appear that the mean temperature of the earth's surface 

 in our climate is under 51°, and even less than 50^ in a considerable 

 portion of these districts. This is from ten to nearly thirty degrees 



