PHYSIOLOGICAL ACTIONS OF DRUGS ON. THE SECRETION OF BILE. 135 
disease. The experiments on the healthy liver of the dog, on the normal, and 
on the abnormal human liver, are three sets of experiments closely related, but 
still distinct. The facts derived from any one of the three cannot be substituted 
for those of the other two. Each set of facts has its own proper place, and 
must be carefully kept there. When, therefore, we show by the physiological 
“method that such substances as sodium benzoate, sodium salicylate, ammonium 
phosphate, and others, powerfully stimulate the liver of a dog, we do not for a 
moment say to the clinical observer, you will find that these things have a 
similar action in man. We merely say it is likely that they also act thus in 
man; experiment with them in his case, and tell us if you find that they 
have on him a similar action, and tell us also m what diseased states you find 
- the employment of this or of that substance most advantageous. 
_ All-are agreed that medical science has much to gain from the attainment 
of a precise knowledge of the physiological actions of medicinal agents. The 
action of ipecacuan in dysentery is an apt illustration of this fact. On asking a 
highly experienced Indian physician how he explainéd the appearance of a 
large amount of bile in the dejections after the administration of sixty grains of 
ipecacuan in cases of dysentery, he at once replied, “ My theory is that it 
relieves a spasm of the bile ducts, and thus allows of the escape of pent-up 
bile.” But, when we give sixty grains of ipecacuan to a healthy dog, it never 
fails to cause the liver to secrete a greatly increased quantity of bile. Probably, 
therefore, no one will now be inclined to doubt that in dysentery, ipecacuan 
affects the liver in a similar manner, and that the increased discharge of bile 
is due to its increased secretion, and not to the relief of an imaginary spasm of 
the bile ducts. It must be admitted that the attainment of this precise know- 
ledge regarding the action of ipecacuan does not reveal to us the true pathology 
of dysentery, but it places us one step nearer to a knowledge of it; for once 
we know the action of a drug in a healthy state of the body, and find that 
| a diseased state is cured by that action, our knowledge of the nature of the 
diseased state is necessarily advanced. 
While all have admitted the limited and unsatisfactory character of our 
| knowledge of the effects of drugs on the liver, several investigators have 
attempted to advance the subject by the physiological method of experi- 
_ menting with drugs on animals. Nearly all the observations have been made 
| on the dog—that being the animal best suited for the purpose. The method 
| resorted to by the earlier experimenters was that of continuously collecting the 
| bile from a permanent biliary fistula, and observing how its amount and com- 
| position were affected by drugs. A permanent biliary fistula is established by 
oceluding the common bile duct, and establishing.a communication between 
the fundus of the gall-bladder and the exterior of the abdomen. When the 
wound in the abdominal wall has completely healed, and nothing remains but 
