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ORIGINAL COMMUNICATIONS. 
is more favorable for those who believe in the possibility of 
judging of the virtues of plants from their exterior conforma- 
tion."* 
Forms of exhibition. — The root has been administered in 
powder and decoction, from its little activity; the former 
may be given in doses of forty grains, or a drachm. The 
decoction has already been mentioned as a remedy in gravel. 
It may be made by adding a pint of water to the ounce of 
powered root An extract has been proposed, which, in com- 
bination, might be made useful. Such an extract is spoken 
of by the late Prof. Barton as little inferior to the scammony 
of the shops. It is consonant with experiment, however, 
to suppose that diluted alcohol constitutes the appropriate 
menstruum. 
♦We have been informed by Dr. Skinner, who resided for a number of 
years, as the Governor of Liberia, on the West Coast of Africa, that he 
there met with a species of Convolvulus having a large root, which 
possessed properties so active as to produce purging and inflammation of 
the intestines of hogs, who happened to eat it. J. C. 
