446 THE SOLIDS. 



" The arteries in this stage are so difficult to inject, that some ana- 

 tomists have denied the possibility of the operation. The difficulty has its 

 origin in the great pressure, which is exerted on the whole of the arterial 

 system, by the contraction and hardening of the organ. 



" Veins. The veins in this stage present, on the surface of the organ, 

 the well-known stellated aspect which arises from the gradual pressure 

 exerted on the trunks, and the contraction of the organ. 



Tubuli. The tubuli are larger than in the preceding stage, and are 

 gathered into rounded masses, which form the granules on the surface of 

 the organ. The latter are of a white hue, and are most commonly fully 

 distended with fatty depositions ; though not unfrequently they appear 

 like dark spots ; the tubuli, in that case, being full of blood. A rounded 

 appearance is generally characteristic of the granules, in each of which 

 the component tubule forms innumerable convolutions. It is extremely 

 difficult to inject the tubuli from the ureter ; indeed, it is very rarely that 

 it is possible to distend them from this source ; nor is it an easy matter 

 to fill them from the artery, though, as will be seen by the drawings, my 

 efforts have not been without success. 



The tubuli are filled with oily cells, granular matter, particles of various 

 sizes, and blood globules. 



" Parenchyma. The parenchyma is hard, and is composed of elongated 

 stellated cells, from the angles of which fine threads proceed, and com- 

 municate with each other." 



The researches of Mr. Simon and Dr. Johnson, which ap- 

 peared simultaneously in the Transactions of the Medico- 

 Chirurgical Society for 1847, have brought to light other 

 facts in the pathology of the kidneys. It is proposed in the 

 next place to give an abstract of the observations of each of 

 these observers, couched, as far as possible, in the language of 

 the authors. 



Mr. Simon's paper is entitled " On Subacute Inflammation 

 of the Kidney." 



" Without dwelling on those excessively rare cases, where idiopathic 

 nephritis (independent of tubercles or of calculus) may, by its mere in- 

 tensity, have ended in large suppuration or (almost uniquely) in gan- 

 grene, I may state that, in an infinite majority of instances, inflammation 

 of the kidneys is subacute. It depends on some humoral derangement 

 of the entire system, and commences as functional excitement manifest 

 in an act of over-secretion. The morbid material which thus stimulates 

 the kidney in its struggle for elimination will sometimes consist of pro- 

 ducts of faulty digestion, the lithates or the oxalates; sometimes of 

 matters cast upon the kidney in consequence of suppressed function in 



