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Selected Articles. 
M. Payen could not have repeated this process, or like m, 
he would have found that this white powder is formed of the 
sulphates of potash and magnesia, carbonates of potash and 
lime, phosphates and acetates, 
Hyoscyamus also contains much fatty oil, a peculiar resin, 
woody fibre and gum. 
We conclude from the above that hyoscyamine has not as 
yet been isolated, and that the white substance which has 
been mistaken for it is a mixture of various mineral salts. 
The acro-narcotic properties of hyoscyamus are probably 
owing to a union of all the principles composing it. — Journ. 
de Pharm. 
ART. XLVI. MODES OF DETECTING THE EXISTENCE OF SUL- 
PHUROUS ACID IN THE HYDROCHLORIC ACID OF COM- 
MERCE. By J. Girardin, Professor of Chemistry at Rouen. 
The hydrochloric acid of commerce is far from being pure. 
It is always of a yellow colour from an admixture of the per- 
chloride of iron, which results from the action of the hydro- 
chloric acid gas on the cylinders in which it is made. It also 
often contains chlorine and hyponitric acid which likewise 
tend to colour it. It generally contains variable proportions 
of sulphuric acid, or small quantities of sulphate of soda and 
lime. Finally, it is frequently adulterated with sulphurous 
acid. 
Of all the foreign matters spoken of above, the last is by 
far the most injurious, and more especially where the hydro- 
chloric acid is used for the manufacture of chlorine, the chlo- 
rites, and the hydrochlorate of tin ; and hence it is extremely 
important to be able to recognise with ease and certainty the 
least traces of this adulteration. 
The methods hitherto devised do not fulfil these indications. 
That cited by M. M. Bussy and Boutron Charlard, in their 
" Traite des moyens de reconnaitre les falsifications des drogues 
