ON THE ACTION OF MERCURY ON THE BILIARY SECRETION. 191] 
first or second hour after feeding, the other so much the earlier the more 
scanty the supply of food. 
In Bidder and Schmidt’s tabulated observations on the first dog, it will be 
seen that the greatest amount of fresh bile was secreted between six and 
seven hours after a meal. It is true that the greater amount of dry biliary 
residue was found in one of the collections made from fourteen and a half to 
fifteen and a half hours after feeding; but in another quantity collected at 
the same period after feeding the amount both of fresh bile and dry residue 
was much less than that coll-cted between six and seven hours after a meal. 
Again, of two quantities collected respectively on the 21d and 6th of Novem- 
ber, from fourteen to fifteen and a half hours after feeding, the amount of 
fresh bile in the first collection was only about the half of what was secreted 
from three to four hours after a meal; and in the second collection it was 
about half of that secreted from four and a half to five and a half hours after 
a meal. The tabulated observations on the third dog seem to give moze 
support to Bidder and Schmidt’s opinion ; but quantities of biliary secretion 
given for different periods after feeding are too fluctuating to permit the 
amount of bile secreted at any given stage of digestion to be accurately 
estimated. The observations of Bidder and Schmidt themselves, therefore, 
do not support their own conclusion; and as this is opposed to those of 
other experimenters, it must be concluded that the amount of bile secreted 
varies considerably in the same animal, and at the same period of digestion, 
even independently of food and drink. 
Arynoip*.—In 1854 Dr. Arnold published a work on the ‘ Physiology of 
the Bile,’ and afterwards made some additional experiments on the subject in 
1857. The apparatus he employed consisted of a canula 43 centimetres long 
and 4 centimetres wide, attached by a screw to an elastic caoutchouc bag 10 
centimetres long and 1 centimetre broad. Fifteen millimetres above this 
attachment, and at right angles with the canula, was a metallic plate, 12 
millimetres in diameter. This plate was placed between the skin and the 
muscles ; and the wound healed perfectly over it, preventing all escape of bile 
between the soft parts and the canula. The distal ‘extremity of the bag had 
a cork stopper, by taking out which the bile collected in it could be removed. 
The operation was performed in the usual manner on a healthy doz of middle 
size, weighing 9-250 kilogrammes, on the 18th of June, 1853. The common 
duct was first tied close to the duodenum, and again half an inch from the 
eut. The portion between the two ligatures was then excised. Although 
after the operation the dog was exhausted, and yomited its food more than 
once, on the following day he appeared to be quite well. The bile flowed 
freely through the canula until July Ist, when it ceased. Another and 
wider canula, with a broader border, was then inserted. This also, sub- 
sequently, was so forced forwards by the contzaction of the wound that no 
bile could flow, and the canula was withdrawn. The apparatus first in- 
serted was then employed, and answered perfectly, as the canula was firmly 
fixed in its place by the wound healing over it; so that not a drop of bile 
escaped at its edges. From the 18th of June until the 6th of July, the dog 
was fed on bread, milk, flesh, and potatoes. It lost 375 grammes in weight 
during this period, without any perceptible derangement of digestion. The 
feces were pultaceous, without any trace of bile-pigment, had a putrid 
odour, and contained a considerable quantity of fat, but no wace of mascular 
fibre. To prevent him from licking the bile he was muzzled. From July 
6th to August 2nd he was fed entirely on flesh. From the 6th to the 9th 
* Zur Physiologie der Galle, 4to, Mainz, 1854. 
