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RESINAE— RESINS 

 Resins are chemically solid plant substances or exudations us- 

 ually acid in character, insoluble in water but soluble in water and 

 an alkali. However, the pharmaceutic class — resins — are those 

 plant substances insoluble in water, soluble in alcohol, obtained 

 either as a residue left after the distillation of an oleoresin or by 

 precipitating them by pouring a concentrated alcoholic extract of 

 the drug into water or acidulated water. All official resins, except 

 rosin are obtained in this way. Four are official : 

 Resina Rosin 



Resina Jalapae Resin of Jalap 



Podophylli " " Podophyllum 



" Scammoniae " " Scammony 



Resina Jalapae — Jalap 



Jalap, in No. 60 powder 50.0 Gm. 



Alcohol 



"Water, each, a sufficient quantity 

 Moisten the powder with 25 mils of alcohol and pack it firmly 

 in a cylindrical percolator; then add enough alcohol to saturate 

 the powder and leave a stratum above it. When the liquid begins 

 to drop from the percolator, close the lower orifice, and, having 

 closely covered the percolator, macerate for 48 hours. Then allow 

 the percolation to proceed slowly, gradually adding alcohol, (until 

 250 mils of percolate are obtained) or until the percolate 

 ceases to produce more than a slight turbidity when dropped 

 into water. Distil off the alcohol, by means of a water-bath, until 

 the percolate is reduced by weight to 12.5 grams, and add the latter 

 slowly, with constant stirring, to 150 mils of water. When the pr.e- 

 eipitate has subsided, decant the supernatent liquid, and wash the 

 precipitate twice, by decantation with fresh portions of hot water. 

 After having drained off the liquid, transfer the Resin to a por- 

 celain dish and heat it to dryness on a water-bath. 



Description -. — Yellow to brown masses or fragments, breaking 

 with a resinous, glossy fracture, translucent at the edge, or a yel- 

 lowish-brown powder, having a slight peculiar odor, and a some- 

 what acrid taste. 



