THEIR AMOUNT OF ALBUMEN. 315 



transudations become, however, slightly turbid when very much 

 diluted with water. Scherer* has especially directed attention to 

 transudations of this kind ; they are generally such as were not 

 submitted to analysis till long after their separation, or such as are 

 found in certain morbid processes, in which the alkali of the blood 

 is diminished or has been saturated by the occurrence of an acid. 

 It follows from these experiments of Scherer's, that the mere chemi- 

 cal analysis of transudations is in itself of little scientific value ; 

 and if we would draw any conclusion regarding the pathologico- 

 chemical process from such an analysis, it is imperatively necessary 

 that we should simultaneously institute a comparative analysis of 

 the blood of the patient from whom the transudation was obtained. 

 This is, moreover, one of the reasons why so very few of the 

 analyses of morbid products at present in our possession can be 

 applied to any scientific purpose. 



The quantity of albumen in different transudations is extra- 

 ordinarily variable ; in some transudations, the amount is so small 

 that some observers have believed it to be entirely absent, as, for 

 instance, in the tears, in the aqueous humor of the eye, in the 

 liquor amnii (in the last stage of pregnancy), in the fluid in the 

 lateral ventricles and the spinal canal (in the normal and in 

 the dropsical state), and in the fluid of the cellular tissue in oedema 

 of the extremities. If, however, albumen is never entirely absent 

 in these fluids, its amount in other freshly transuded fluids never 

 reaches that contained in the serum of the blood. It now 

 becomes a question, whether there are any conditions inducing a 

 more copious or a diminished transudation of albumen through 

 the walls of the capillaries, so that certain general rules, if not 

 laws, can be established, in accordance with which there may 

 be an augmentation or a diminution of the albumen in the 

 transudation. 



The following is one of these rules: The quantity of 

 albumen contained in a transudation is dependent on the system 

 of capillaries, through which the transudation occurs. We are 

 indebted to the admirable investigations of C. Schmidtf for our 

 knowledge of this rule, which is equally important in the elucida- 

 tion of the mechanical metamorphosis of matter, and in the 

 explanation of morbid processes ; and at which he arrived by a 

 series of carefully conducted parallel analyses of normal and 

 abnormal transudations. Schmidt assumes, that the transudation 

 from every group of capillaries contains a definite and constant 



* Pathol. Untersuchungen. S. 78. 



f Charaktcristik der Cholera. S. Ho. 



