ra'bi-ez, an infectious disease of man and many other animals. It is a well accepted theory of medicine that a number of diseases such as typhoid, yellow fever, smallpox, cholera, and measles are caused by the presence in the system of colonies of bacteria, for the nature of which the reader is referred to the article on BACTERIUM. Recent investigations have added rabies to this list of diseases. The bacteria of rabies flourish only in animals, chiefly in the brain, spinal chord, nerve trunks, and the salivary glands. An animal cannot have rabies without receiving bacteria from some afflicted animal. This is most likely to happen when an animal with rabies bites another, in which case, bacteria-laden saliva becomes mixed with the blood of the victim. In the case of a person thus bitten, unfavorable symptoms are not likely to appear for the next three or six months and sometimes longer; that is to say, the bacteria require that time to increase sufficiently in numbers to affect the brain. The outbreak usually begins with restlessness, headache, and difficulty in swallowing. Two or three days later twitchings of the muscles and convulsions are succeeded by an increase in the pulse rate and a rise of temperature. Then comes delirium, followed by paralysis and death. Few recover after the disease has reached a malignant stage. One hundred and forty-three deaths of persons are reported in the United States for the year ending May 31, 1890. Both men and animals afflicted with rabies dread the appearance of water or any other liquid; hence the term, hydrophobia, or water-fear. Rabies develops in some animals, particularly rabbits, inside of a week. If it is suspected that a patient is afflicted with hydrophobia, a test is made by injecting blood from his body into that of several rabbits. If none of them go mad within ten days, the presumption is that the patient does not have hydrophobia; if, on the contrary, the rabbits develop the disease, heroic measures must be taken at once. A course of treatment discovered by Louis Pasteur, an eminent scientist of France, has been widely advertised as pasteurism. Taking a hint from the treatment of smallpox by inoculation, Dr. Pasteur inoculated patients with rabies virus from rabbits. He prepared a series of inoculating material from the nerve chord of a rabbit. The first injection was exceedingly weak, merely a trace. As soon as the lymph had killed off these germs, that is to say, as soon as the patient's system had withstood this inoculation, he made another, a little stronger, and later, another stronger again, until before the time had arrived when the patient would naturally have gone mad, his system had become accustomed to rabies virus of full strength. It is claimed that, out of hundreds of cases, this famous man has not lost a patient that began to take treatment within a reasonable length of time after being bitten. Similar institutes have been established in various large cities. The disease was described by Aristotle. It appears to have undergone no material change for 2,000 years. It takes two forms. An animal affected with the more virulent rabies snaps and bites in a rage at whatever or whoever comes in the way. The milder type, or dumb rabies, as it is called, is accompanied by a dropping of the jaw, melancholy, and extreme dejection, without any desire to attack others. Sheep, horses, cattle, dogs, wolves, foxes, rabbits, chickens, probably all warm-blooded animals, are subject to rabies, but it is most dangerous in the case of a dog, from the tendency which a mad dog has to spring at anyone within reach. There is a foolish notion not yet entirely eradicated that a dog who has bitten a person should be killed, lest the person go mad. A dog cannot communicate hydrophobia unless the bacteria be in its own blood and saliva at the time of the biting. The fact that the dog may subsequently have rabies and go mad does not endanger a person bitten before the dog was infected. The bite of a person or of any animal afflicted with rabies is just as dangerous as that of a dog. See JENNER; SMALLPOX.