riy6 Intelligence and Miscellaneous Articles. 



in the night of 13-14 November, and we might have conjectured 

 a movement of the node. You will remark that in 1849 the 

 phaenomenon has been most developed again the 12-13, such as 

 M. Bonpland and I observed it half a century ago. The October 

 stream, which has been observed this year, from 15-17 October, is 

 independent of the November stream, since they have both been seen 

 in the same year 1849. It is remarkable that the Arabian writers 

 also notice two enormous falls, one of the 19 October 1202 (Fraehn, 

 in the Bulletin de V Academic de Saint P4tersbourg , t. iii. p. 308), 

 and the other, October 902, on the night of the decease of King 

 Ibrahim-ben- Ahmed (Conde, Historia de la dominacion delos Arabes, 

 p. 346.). M. Sedillot might find the precise date of the death of 

 this king. I think that many apparent anomalies are explained, if 

 we admit that the stream is of a certain magnitude, a variable magni- 

 tude ; and that the asteroids, in the annular zone, are unequally 

 distanced and agglomerated. Have we not seen the comet of Biela 

 divide into two comets, since December 19, 1845, each having its 

 tail, advancing parallel at twenty minutes distance from one another ! 

 Cosmical nebulae, that have so little mass, such as comets, fire-balls, 

 and shooting stars, must be subject to undergo many transforma- 

 tions in form, direction and velocity. 



ON TEREBIC ACID. BY M. A. CAILLOT. 



M. A. Caillot, Professor of Medicine at Strasburgh, has obtained 

 a new product which he calls terebic acid, by treating oil of turpen- 

 tine with nitric acid. 



This acid, under the influence of heat, as also all other acids, the 

 temperature of which may be raised from 266° to 275° F., is con- 

 verted into carbonic acid and pyro-terebic acid. 



The formula of this acid uncombined is C" H'" O* : it produces 

 several kinds of salts. 



A. Monobasic salts : the formula of these is C**H* O'', MO ; they are 

 soluble in water and crystallizable. They are obtained by treating 

 terebic acid with insoluble carbonates, or by double decomposition. 



B. Terebic acid forms other saline compounds which contain 2 

 equivalents of base for the 14 equivalents of carbon contained in the 

 acid. If the circumstances resembled common bibasic acids, the for- 

 mula of these salts would be C'*H*0^ 2M0. M. Caillot obtained 

 only one thus constituted ; it was an insoluble salt of lead. 



In all the other bibasic salts, the water of the terebic acid, instead 

 of being eliminated, remains in the salts, or even with certain bases, 

 three equivalents are added. This water is essential to the consti- 

 tution of the salt, for it cannot be expelled without disengaging 

 pyrogenous compounds at the same time. 



Adopting the generally received opinions of science, we are led to 

 admit the existence of two new acids, both of them bibasic ; one of 

 these, which the author calls diaterebic acid, is represented by the 

 formula C'H"' 0^-|-2H0 ; the other, which he names metaierebic 

 acid, has the formula C"H'*0"-i-2H0. 



