386 Schweinfurt Green. 



rated in a capsule to dryness. This residuum weighed 

 two drams. It was of a brownish red, intermingled with 

 brilliant specks, and had a pungent and styptic taste. It 

 was soluble in water, and its odour was that of native 

 Rhubarb. 



I presurne that this preparation will be useful in medi- 

 cine, and will deserve the attention of physicians. 1st, be- 

 cause the different kinds of Rhubarb have qualities so va- 

 rious, that in many cases the ordinary dose is very uncer- 

 tain. 2d. because this extract will be of uniform strength 

 wherever the same process is followed. 3d. because it may be 

 given very safely in solution even to new born infants to 

 evacuate the meconium, one or two grains will be suffi- 

 cient for this purpose. 4th, because the remedy is thus de- 

 prived of its ligneous and mucous portions, which if notia- 

 jurious, are at least useless. 



I shall esteem myself happy if the process which I have 

 thus pointed out, shall furnish a new resource to the heal- 

 ing art ; and if those of my brethren who have its progress 

 at heart, shall concur with me in introducing this prepara- 

 tion into the practice of physic. 



Bib. Univ. July, 1823. 



22. Schweinfurt Green. — Dr. Liebig, in the Annales de 

 Chimie of August 1823, states that the preparation of this 

 fine colour, as recommended by Braconnot, being tedious 

 and expensive, the following is much preferable. 



Dissolve in a copper kettle by heat, one part of verdi- 

 gris in a sufficient quantity of pure vinegar, and add to 

 it an aqueous solution of one part of white arsenic; a precip- 

 itate of dirty green generally forms, which must be dispelled 

 by adding more vinegar until the precipitate is perfectly dis- 

 solved. 



Boil the mixture, and after a time, a granular precipitate 

 will form, of the most beautiful green, which being separa- 

 ted from the liquid, well washed and dried, is nothing more 

 nor less than the colour sought for. If after this, the liquor 

 contains copper, more arsenic may be added; and if it con- 

 tains an excess of arsenic, more copper may be added, and 

 the process repeated. It often happens that the liquid con- 

 tains an excess of acetic acid. ' It may then be employed 

 ior dissolving more verdigris. 



