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nature of an anastomosis, yet in such a manner as 

 occasionally affords a passage to blood, to pus, and to 

 calculi ; it is easy, moreover, to fill the bladder through 

 them with air or water ; but by no effort can you force 

 anything from the bladder into them. I care not, 

 however, to make any question here of the etymology 

 of words ; for I am not of opinion that it is the province 

 of philosophy to infer aught as to the works of nature 

 from the signification of words, or to cite anatomical 

 disquisitions before the grammatical tribunal. Our 

 business is not so much to inquire what a word properly 

 signifies, as how it is commonly understood ; for use 

 and wont, as in so many other matters, are greatly 

 to be considered in the interpretation of words. It 

 seems to me, therefore, that we are to take especial 

 care not to employ any unusual words, or any common 

 ones already familiarly used, in a sense which is not in 

 accordance with the meaning we purpose to attach to 

 them. You indeed counsel well when you say, " only 

 make sure of the thing, call it what you will." But 

 when we discover that a thing has hitherto been in- 

 differently or incorrectly explained (as the sequel will 

 show it to have been in the present case), I do not 

 think that the old appellation can ever be well applied 

 to the new fact ; by using the old term you are apt to 

 mislead where you desire to instruct. I acknowledge, 

 then, a transit of the blood from the arteries into the 

 veins, and that occasionally immediate, without any 

 intervention of soft parts ; but it does not take place 

 in the manner hitherto believed, and as you yourself 

 would have it, where you say that anastomoses, correctly 

 speaking, rather than an anastomosis, were required, 

 namely, that the vessels may be open on either hand, 

 and give free passage to the blood hither and thither. 

 And hence it comes that you fail in the right solution 

 of the question, when you ask how it happens that with 

 the arteries as patent or pervious as the veins, the 

 blood nevertheless flows only from the former into 



