LESIONS.--If the congestion has not existed for a long time, we find the kidneys increased in size and their weight great in proportion to their size. They are of an unnatural hardness--a hardness which can be imitated by injecting the blood-vessels of a normal kidney with water. The capsules are not adherent, the surfaces of the kidneys are smooth. Both the cortical and pyramidal portions are congested, and this congestion gives the entire organs a peculiar reddish, livid color. No lesions are found in the Malpighian bodies, tubes, stroma, or blood-vessels, except that the epithelium of the convoluted tubes may be a little swollen. If the congestion has lasted for a longer time, the kidneys may continue to be large or they may be somewhat reduced in size; the weight remains out of proportion to the size. There are the same unnatural color and consistence. The capsules are now often slightly adherent and the surfaces of the kidneys finely nodular. In the cortex there may be patches of new connective tissue enclosing atrophied tubules, or there may be a more diffuse growth of connective tissue separating the tubes from each other. In the convoluted tubules the epithelial cells may be swollen and finely granular, or very much swollen and coarsely granular, so as to nearly fill the tubes, or flattened so that the cavities of the tubes are {70} unnaturally large. The tubes may also contain cast-matter and detached and broken epithelial cells. The capsules of the Malpighian bodies may be a little thickened and the capsular endothelium swollen. In the pyramids the epithelium of the straight tubes may be granular and detached, and there is often cast-matter in the looped tubes. It is difficult to tell whether there is any real change in the veins of the kidney. As a result of the same interference with the venous circulation, similar changes are found in other parts of the body--in the lungs, liver, spleen, stomach, small intestine, and pia mater. In all these organs there is, first, simply a venous congestion, then after a time structural changes are added. Formation of new connective tissue and of new functional cells of the particular organ, degeneration of these cells, dilatation and tortuousness of the small veins and capillaries, are regularly present. The kidney lesion, therefore, is only one of a number of lesions, all dependent on a common mechanical cause. SYMPTOMS.--Of the persons who die with chronic congestion of the kidney, a large number present marked symptoms during life, but it is difficult to determine how largely these symptoms are due to the congestion of the kidney.