=INFLAMMATION OF THE BLADDER= (_Cystitis_).--The condition which we describe under this head commonly causes frequent painful urination. Primarily there is usually some agency which mechanically or chemically irritates the bladder, and if the irritation does not subside, inflammation follows owing to the entrance of germs in some manner. The introduction into the bladder of unboiled, and therefore unclean, instruments is a cause; another cause is failure to pass urine for a long period, from a feeling of delicacy in some persons when in unfavorable surroundings. Nervous spasm of the urinary passage from pain, injuries, and surgical operations constitutes another cause. Inflammation may extend from neighboring parts and attack the bladder, as in gonorrhea, and in various inflammations of the sexual organs of women, as in childbed infection. Certain foods, waters, and drinks, as alcohol in large amounts, and drugs, as turpentine or cantharides applied externally or given internally, may lead to irritation of the bladder. Exposure to cold in susceptible persons is frequently a source of cystitis, as well as external blows and injuries. The foregoing causes are apt to bring on sudden or acute attacks of bladder trouble, but often the disease comes on slowly and is continuous or chronic. Among the causes of chronic cystitis, in men over fifty, is obstruction to the outflow of urine from enlargement of the prostate gland, which blocks the exit from the bladder. In young men, narrowing of the urethra, a sequel to gonorrhea, may also cause cystitis; also stone in the bladder or foreign bodies, tumors growing in the bladder, tuberculosis of the organ. Paralysis of the bladder, which renders the organ incapable of emptying itself, thus retaining some fermenting urine, is another cause of bladder inflammation. =Symptoms.=--The combination of frequency of and pain during urination, with the appearance of blood or white cloudiness and sediment in the urine, are evidences of the existence of inflammation of the bladder. The trouble is aggravated by standing, jolting, or active exercise. The pain may be felt either at the beginning or end of urination. There is also generally a feeling of weight and heaviness low down in the belly, or about the lower part of the bowel. Blood is not frequently present, but the urine is not clear, if there is much inflammation, but deposits a white and often slimy sediment on standing. In chronic inflammation of the bladder the urine often has a foul odor and smells of ammonia.