Besides pressure, the most frequent cause of bed-sores is constant moisture from the passage of urine and motions and consequent damping of the sheets. Great care must be taken to thoroughly dry the back after any evacuation; the lower part of the back should be dusted with a powder of boric acid and zinc oxide. If a bed-sore is present the patient should lie on a circular pad with a hole in the middle, to take pressure off the bed-sore. The sore should be thoroughly cleaned twice a day with some antiseptic lotion, such as chinosol or permanganate, and subsequently dressed with zinc ointment or vaseline. If the bed-sore is on the back, the patient should lie if possible on each side alternately, to relieve the pressure. _Beri-beri._ In most cases this is a disease due to some deficiency in the dietary, which leads to a form of what is called peripheral neuritis. The name is possibly derived from a Cingalese word signifying “I cannot.” _Symptoms._—Weakness of the legs and digestive troubles, abnormal sensations in the legs, frequently associated with swelling. The gait alters, and the arms and fingers may be affected. The condition is one of spreading paralysis, and in bad cases the heart is affected. In so-called wet beri-beri the patient becomes bloated as in dropsy, while in dry beri-beri he wastes away until he is little better than a skeleton. There is a “squatting test” which may enable one to recognize the disease at an early stage. The patient, with his hands on the top of his head, is unable to assume a squatting position and to rise from it unaided. If he is squatting and has to rise he accomplishes the act by climbing, as it were, up his own legs. _Prophylaxis._—Avoid overcrowding, as this seems in some cases to predispose to the disease. Give the yeast extract known as “Marmite,” which is supplied in small cubes one-quarter ounce in weight. One should be taken twice a week, either alone or with bread or biscuit, or dissolved in warm water in the form of a soup. Lentils, other legumes, and oatmeal are useful. Eggs and fresh meat, when obtainable, are very valuable. _Treatment._—This is chiefly dietetic. Give yeast, two ounces daily, along with milk and sugar, or marmite in one-cube doses twice a day. Eggs are specially useful, while fresh milk, legumes, and nourishing soups are all indicated. Only small quantities of food should be given at a time. Rest in bed is very important, and the patient must be careful when he is allowed to get up owing to the danger of heart failure. Tonics are required during convalescence. _Blackwater Fever._