mical Com 



(J78 AROIBE^. 



extended epiblema-cells or of a brown corky tissue, tlie latter occurrinf 

 in tlie parts free from leaf-scars. The prevailing tissue, both of the 

 outer and the central part, consists of uniform nearly globular cells, 

 traversed by numerous vascular bundles, especially at the boundary 

 line (medullary sheath). Besides them, the rootstock like that of mauy 

 fresh- water plants, exhibits a large number of intercellular holes. These 

 air-holes, or more correctly water-holes, are somewhat longitudinally 

 extended, so as to form a kind of net-work, imparting a spongy con- 

 sistence' to the fresh rootstock. At certain places, where the series of 

 cells cross one another, especially in the outer part, there are single 

 cells filled with essential oil,^ which may be made very conspicuous by 

 adding to sections dilute potash or perchloride of iron. The other cells 

 are loaded with small starch granules ; a little mucilage and tannic 

 matter is met with in the exterior coat. 



_)osition — The dried rhizome yielded us 1'3 per 

 cent, of a yellowish neutral essential oil of agreeable odour, which in a 

 column of 50 mm. long, deviates 13-8° to the right. By working on a 

 large scale, Alessrs. Schimmel & Co., Leipzig, obtain 2-4 to 2-6 per 



CGDti, 



nm^T^^}"^^ ^"^ Kurbatow (1873), this oil contains a hydrocarbon, 

 ^ a , boilmg at 159° C, and forming a crvstalline compound with HCI, 

 and another hydrocarbon boiling at 255-258° C, affording no crystal- 

 li^^able hydrochloric compound. By submitting the oil to fractional 

 distillation, we noticed, above 250°, a blue portion, which may be de- 

 colorized by sodium. The crude oil acquires a dark brownish colour 

 on addition of perchloride of iron, but is not at all soluble in concen- 

 trated potash solution. 



The bitter principle AcoHn was extracted by Faust in 1867, as a 

 semmuid, brownish glucosidc, containing nitrogen, soluble both in ether 

 and m alcohol, but neither in benzol nor in water. In order to obtain 

 tins substance, we precipitated the decoction of 10 lb. of the drug by 

 means ot tannic acid, and followed the method commonly practised in 



w-fi?''?i^''^t^°'^ ""^ ^^^^^^ principles. By finally exhausting the residue 

 w h chloroform, we succeeded in obtaining a very bitter, perfectly 

 crystalline body, but in so minute a quantity, that we were unable to 

 investigate its nature. ^ 



n«o P?^^~^f ^et Flag is an aromatic stimulant and tonic, now rarely 

 hrZ '""/^S^^^^ medicine. It is sold by the herbalist for flavouring 

 hTjr. ff masticating to clear the voice. It is said to be also used 

 t>y snuli manufacturers. 



Adulteration— The rhizome of the Yellow Flag-, Iris Pseuclaconis 

 i^., IS occasionally mixed with that of the Sweet Flag, from which it 

 Siv ^/•'^*l°S^^?,^ed by its want of aroma, astringent taste, dark 

 colour, and dissimdar structure. 



tus MinTs^K'?i^)3 wi'f \^y ^^"'-- J-«-^'« ed. 1867. 376. We suppose tl>e 



(CakmiTs !ivomlkct'^r^nK "*• "'''^r' \- '^'''^ ""^^'^r notice was intended. 

 et Ethiopia ?TTp"^~f/*y '" ^"'^^^ ' Hence the pnicticc of peelm the 



ex parte^onciva ' ' . n' '* ^'f'-^ '''^'^'''^^ ^'l^i^ome which prevails in some parts of 



telcB sunt aranearum'' S ^f^'^'^'l^ *'^'"^ *he Continent ought to be abandoned. 



