46 
ON THE JAMAICA DOGWOOD. 
10. Ordinary Soil and distilled Water. — Results perfectly 
identical with those of the preceding experiment. 
11. Ignited Charcoal reduced to a coarse Powder , Ashes , 
and distilled Water. — All came up, but were far less developed 
than in the last three experiments. 
If we glance at the results of these experiments, and leave 
out of question those substances which from some cause or 
other were injurious to germination (experiments 4 and 5,) it 
appears, — -a, that rain-water and atmospheric air do not afford 
sufficient nutriment to plants; the inorganic substances are 
wanting; b, that rain-water, ashes and atmospheric air do like- 
wise not suffice ; c, that the aqueous extract of humus contains 
too little organic substance to yield to the plants what they 
require ; d, that ulmic acid prepared from sugar is actually 
advantageous to the growth of plants, although it contains no 
nitrogen ; e, that the humic acid from garden earth is ex- 
tremely advantageous to the growth of plants ; that the am- 
monia compound of this latter., as well as the acid from bog 
earth, produce a luxuriant development ; g, that lastly, plants 
do not succeed so well in wood-charcoal and ash, as in ordi- 
nary soil, or in the substances mentioned in e andy. 
Lond. Chem. Gaz.^from Journ.fiir Prakt. Chem. 
ART. XII.— ON THE JAMAICA DOGWOOD. 
Dr. Hamilton, during a visit to the Antilles, was 
struck by the powerful narcotic effects on fish pro- 
duce by the bark of the roots of the Piscidia erythrina, 
or Jamaica dogwood. Thinking that this might be of 
utility as a medicine, he found that the tincture, prepared 
by macerating the bark of the roots gathered during the 
period of inflorescence, and before the appearance of the 
