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less costly. | The imported Cannabis varies extremely in 
activity and much of it is practically inert or flagrantly 
adulterated; so that the greatest watchfulness is necessary 
to insure getting a drug of good quality. We test our 
products of Cannabis physiologically—on dogs; this 1s 
essential, for the chemical estimation of the resin is no guide 
to the value of the drug. A standard dose of the lot to 
be tested is administered in capsule to a dog of average 
nervous sensibility. The effect of this dose is carefully 
compared with that of a similar dose of standard Cannabis 
administered to another dog at the same time and under the 
same conditions. The doses are then reversed; that is, the 
dog that has received the test dose receives a dose of the 
‘standard drug, and a second observation is made. A test 
dose is finally reached that will produce the same action as 
the dose of the standard; and the amount of dilution or 
concentration necessary to bring the tested product to the - 
required strength is determined. The degree of accuracy 
with which the test is carried out depends largely upon the ~ 
experience and care of the observer. 
