PRUDDEN, T. M., M.D. TUBERCULOSIS AND ITS PREVENTION In Nature an extremely important part is played by minute organisms. Some of them take up their abode in the human body and there set up diseases of which consumption is the chief. The tubercle bacillus is the sole cause of consumption: its entrance may be prevented, mainly by destroying the spittle of patients. Susceptibility to consumption may be inherited: the disease itself is not. Any cause which lowers vitality increases susceptibility. Dust is a source of danger both out-of-doors and in. Dust in houses should be removed, not simply stirred up. Encouragement for sufferers in early stages of disease. 63 STERNBERG, G. M., M.D. MALARIA AND MOSQUITOES Malaria, long believed to be due to bad air, is really chargeable to a mosquito discovered by Dr. Laveran, 1880, and first detected in America by Dr. Sternberg, 1886. Healthy individuals inoculated with blood containing the parasite develop malarial fever. The mosquito theory of infection was advanced by Dr. A. F. A. King, Washington, 1883. Dr. Manson and Dr. Ross confirmed the theory by observation and experiment. Five individuals exposed to the July air of the Roman Campagna escape malaria by using screens on doors and windows and nets over their beds. 89 ROOSE, ROBSON, M.D. THE ART OF PROLONGING LIFE What is the natural term of life? One hundred years the extreme limit. Longevity runs in families. Clergymen are long-lived. Abstemiousness, sound digestion, capacity for sleep usually found in the long-lived. Work is healthy, especially intellectual work. Reasonable hobbies are good. Beyond middle life exercise should be judicious. Diet should be digestible and moderate. Clothing should be sensible and cleanliness habitual. 107 RICHARDSON, B. W., M.D. NATURAL LIFE AND DEATH Man should be as unconscious of death as of birth. To this end let him observe the rules of Health. RULES OF HEALTH The health of the unborn should be ensured. Many diseases usual in children may be avoided by isolation and disinfection. An equable temperature should be maintained. Regular and various mental labour is a benefit. Physical exercise should be moderate. The passions should obey the reason. Alcohol and tobacco are harmful. Opium, and other narcotics should be shunned. Not too much meat. Water the natural beverage. Air should be pure and not damp. Rest and recreation gainful. Idleness injurious. Sleep should be adequate. 137 COLTON, BUEL P. CARE OF THE EYES