Selected monographs.

Date:: 1888

Catalogue details

Licence: Public Domain Mark

Credit: Selected monographs. Source: Wellcome Collection.

51/440 (page 35)

the assumption tliat under normal conditions a fluid extremely poor in albumen transudes into Bowman-Miiller's ■capsules, and that physiological albuminuria is dependent upon the albuminous contents of this fluid. An assumption certainly is not equivalent to a direct proof, but, in the absence of any such, is perfectly justifiable so long as it cannot be shown that there is any error in the facts upon which it is based, or that experiences and analogies are unjustly brought forward in support, or lastly, until we have direct proof to the contrary. Not long ago it was regarded as impossible, by direct observation or examination, to prove whether the fluid contained in the Bowman-Miiller's capsules is albuminous or not. To Posner is due the credit of having indicated a method of directly observing that transudation by an improved method of boiling—and to him we are indebted for the positive proof that in many cases of pathological albuminuria the source of the albuminous secretion is to be found in the glomerular vessels—a fact which until recently could only be guessed at with more or less probability. But Posner has gone further than this, for he believes that he has positive proof for his assertion that the kidneys under normal conditions are not albuminuric, that is, that no albuminous substances transude from the blood-vessels of the glomeruh. He holds this opinion, because in normal kidneys he has not been able to detect any excretion of albumen in the capsules, but he manifestly over-estimates the efficiency, as a test, of the method of boiling and of the micro- scope. For there is no doubt that albumen may be and is present without becoming visible after boiling.^ I will not discuss the fact that in normal kidneys, even after boiling, no trace of coagulated albumen can be discovered in the lym- phatics, which, according to Ludwig and Zawarykin (40), surround the vessels and the urinary tubules, and, according to Eyndowaky, (41) probably enter the capsules and wind round the glomerular vessels. Can there be any doubt of the presence of lymph and albumen, simply because they are invisible ? But more than this ; albuminuria can be induced in various ways, and the most minute examination laay fail to ' What is true of boiling tolds good also with regard to hardening and <3oagulation by alcohol.