324 Intelligence and Miscellaneous Articles. 



be fossil. This maize is in isolated grains, sometimes agglomerated 

 but without any apparent order; they were found in the state of 

 Kentucky, in a district of alluvium , at a depth of five or six feet, in 

 layers from eight to ten inches thick, and extended from four to five 

 miles along the Ohio and its tributary the Fish Creek, 25 miles below 

 "Wheeling. — Journal de Pharmacie, Jan. 1837. 



VEGETATION IN A SOLUTION OF ARSENIC. 



M. Gilgenkrantz has seen a plant of the genus Leptomitus, or 

 HygrocrociSi form in a solution of arsenic. This observation, com- 

 municated by M. Bory St. -Vincent, proves that arsenic, a substance 

 so very poisonous, and supposed to he destructive to all organized 

 bodies, is however favourable to the vegetation of some plants. 

 M. Bory St.- Vincent mentioned on this occasion that M. Dutrochet 

 had observed about ten years ago the development of a similar plant 

 in a solution of acetate of lead. — Ibid, 



INDIGO. 



Sulphindylic acid, — Analogy of alcohol and indigOy considered in 

 their combination tvith sulphuric acid. 

 M. Dumas read a paper on indigo. This chemist repeated the 

 analysis of indigo, and has obtained precisely the same results as 

 those he arrived at fifteen years back. His analysis gives for the 

 composition of indigo : 



Carbon 7 SO 



Hydrogen 4*0 



Nitrogen 10'8 



Oxygen 12-2 100-0 



The author afterwards endeavoured to determine the nature of 

 the compound which is formed by the action of sulphuric acid upon 

 indigo. It is known that sulphuric acid has the property of dissolv- 

 ing indigo, and of receivingablue colour from this solution. M. Ber- 

 zelius had considered this combination as a kind of emulsion. M. 

 Dumas, on the contrary, supposes it to be a compound analogous to 

 sulphovinic acid j he calls it for this reason sulphindylic acid; it 

 results from a combination of two atoms of sulphuric acid with one 

 atom of indigo. 



This acid forms with potash a salt soluble in water, crystallizing in 

 fine silky lamellae, of a very deep blue: it produces with baryta a salt 

 not very soluble in cold water, but more so when heated. The ana- 

 lysis of these two salts has shown that the formula for indigo is 

 Q2i H'o AZ'^ 0% and that the sulphindylic acid should be represented 

 by 2 SO^-f C30 H'o AZ^ O' j adding to this formula one atom of a 

 base we have that of the sulphindylates. 



It is known that by frequently treating indigo with sulphuric acid 

 a purple matter is formed which is very difficult to isolate from the 

 blue matter. M. Dumas calls this combination sulphopurpuric acid; 

 it is represented by two atoms of indigo and two atoms of sulphuric 

 acid, or of one atom of sulphindylic acid and one atom more of in- 

 digo : it forms with potash a purple salt, soluble in water. 



