COMMON SALT AS A POISON TO PLANTS. 
73 
found to be C 31 H 9 O 10 , and rubiacic acid C 31 H 9 O 16 . Al- 
pha-and beta-resin were next examined, as were also the 
other constituents; and the author then proceeded to exam- 
ine the part which each material plays in the process of 
dyeing ; from which it is satisfactorily proved that alizarine 
is the substance producing colour ; and the advantages of 
converting madder into garancine consist in removing the 
resins and those bodies which are not only useless but in- 
jurious, and in separating alizarine from those salts with 
which it exists in the madder root in close combination. — 
Chem. Gaz. 
ART. XVIII.— ON COMMON SALT AS A POISON TO PLANTS. 
By W. B. Randall. 
The following notice is presented as being likely to afford 
a useful practical caution to those interested in the cultiva- 
tion of plants. In the month of September last, three or 
four small plants in pots were shown to the writer, nearly 
or quite dead ; and he was at the same time informed that 
their destruction was a complete mystery to the party to 
whom they belonged, and that Dr. Lindley had expressed 
his opinion, from the examination of a portion of one sent 
to him, that they were poisoned. Having searched in vain 
for any strong poison in the soil, and in the plants them- 
selves, he inquired more minutely into the circumstances of 
the case, and found that these were only specimens of many 
hundreds of plants both in the open air and in green-houses 
(but all in pots), which exhibited in a greater or less degree, 
the same characteristics. The roots were completely rot- 
ten, so as to be easily crumbled between the fingers; the 
sterns, even in young plants, assumed the appearance of 
old wood, the leaves became brown, first at the point, then 
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