108 
PII A RMA CO GNOS Y. 
Furthermore, in the preparation of oil of peppermint, 
the yield of oil is greater and the quality better if 
the plants are allowed to dry and are distilled im- 
mediately or soon after drying. 
Quite a number of drugs are not infrequently 
observed in commerce in a moldy condition, as tarax- 
acum, veratrum, maranta, aconite, etc. The question 
as to what influence this mold has on the quality of 
the drug has not been cleared up. 
Another cause of inferiority of vegetable drugs is 
lack of sufficient care in garbling. This applies to a 
number of drugs as leaves, where there may be a large 
number of stems and roots; rhizomes and tubers, 
where the proportion of stem-remnants may be exces- 
sive; or in other cases, as cypripedium and hydrastis, 
where roots, which contain much less of the active 
principle, have been found to the extent of 50 per cent. 
A fourth quality influencing the quality of drugs is 
the manner of preservation. While it is generally con- 
ceded that most drugs deteriorate in keeping, still 
this depends largely upon the manner of their preser- 
vation. Thus, the Pharmacopoeia limits the time of 
keeping of ergot and states how it shall be preserved; 
yet a number of writers call attention to the fact that, 
if properly prepared and preserved, the time of keep- 
ing may be very much extended. In order to pre- 
serve ergot, Grover proposed the removal of the oil, 
and Moss found the drug thus treated to retain its 
therapeutic value for six and a half years. Zanon 
suggests placing the drug in alternate layers with sand 
and keeping it in a closely sealed jar. Others grind 
the fresh ergot and preserve with chloroform in par- 
affin paper, while still others first extract the oil with 
alcohol or ether. 
Accidental admixture in the store or warehouse 
