Drinking-cups used in common are another source of [{196}] infection. Let each child have its own tin cup. The clothes-rack in a school also spreads infection. Room enough should be given to each hook to keep the hat and coat of one child from touching those of another, and a wooden partition standing out from the wall about eight inches should separate hook from hook. The janitor should wash the clothes-racks with the acid bichloride solution every time he sweeps.

Suppose a child having diphtheria is found in school, or one is discovered as coming from a house where he was in contact with diphtheria. The discovery is made commonly after the child has been spreading infection for some days. Do not frighten the youngster, but find out from him what parts of the school-building he has been visiting. Then send him and the other children home. Rooms in which the child has not been are not infected, and only that which he has touched is infected in any case. Wet everything in the building and outhouses with which he possibly could have come in contact with the acid bichloride. Burn his books and papers, or, if this action may cause difficulty with parents, let him take his books home and inform the health officer of that fact. When he returns to school be sure of the history of his books. Use formalin or sulphur in the infected rooms, and classes may be begun again the next day. If within the week any child shows signs of sore throat send it home immediately.

Sulphur must be burned when used as a disinfectant, and to be effectual four pounds should be burned for every 1000 cubic feet of air-space in the room. A teaspoonful of sulphur when burned will fill a house with choking, dangerous fumes, but two pounds of sulphur burned in an ordinary bedroom will have no effect whatever on the diphtheria bacillus and very little on any other disease. Sprinkling disinfectants about a house, and setting saucers containing disinfectants in rooms is nonsense—the quantity must be sufficient and be in actual contact with the contagion. A deodorant does not disinfect because it removes a stench.

To burn sulphur set a coal-hod or an old tin pan on two bricks in the middle of the room, but see that there are no [{197}] holes in the bottom of the hod or pan through which burning sulphur could drip to the floor. For a like reason see that the pan is not too narrow nor too shallow. It is safer to set the bricks in a tub filled with water up to the top of the bricks. Use powdered sulphur in preference to the cakes sold by the druggists, and fire this sulphur with a red coal. The room should be moist with steam when the sulphur is set afire so that the fumes will act effectually. Leave it shut tightly for twenty-four hours.

In the Northern States diphtheria is most prevalent in October, November, and December; scarlet fever is an April disease, but it may occur at any time. It is easier to spread the infection of scarlet fever and measles than that of diphtheria, but it is not so difficult to disinfect after scarlet fever and measles as after diphtheria. The contagion of scarlet fever does not resist the fumes of sulphur or formalin. Disinfect a room after scarlet fever as for diphtheria but be sure to use also either sulphur or formalin because the contagion can float about a room. Eruptive contagious diseases like scarlet fever, smallpox, and measles so affect the skin that during convalescence the cuticle scales off. In severe cases of smallpox and scarlet fever the entire outer skin of the hand may peel off like a glove. The contagion is always found in the scaling skin. As the patient grows stronger the scales become finer, until at last they lie as mere mealy dust in the hollows of the elbows or other parts of the body. Down to the very last these scales are infectious, and they will retain the infection for months, probably for a year or more. The scales float in the air of a sick-room, fall on the clothing of visitors, are carried away by the shoes of those that leave the room. The scaling may continue for three weeks—it commonly does. These three diseases are infectious before the scaling begins, sometimes before the rash is well out. A very light attack of any of these diseases in one child may infect another fatally. Insist upon keeping a scarlet fever or measles patient out of school until all scaling has ceased.

Chickenpox is almost a harmless disease, but it is more infectious than even measles. Be cautious with it because [{198}] nearly every epidemic of smallpox begins through some one mistaking smallpox for chickenpox, although there is little or no similarity between the diseases.

A child with tuberculosis of the lungs or a child infected with acute syphilis should not be permitted to go to school under any circumstance.

In the chapter on The Priest in Infectious Diseases will be found an account of the necessity of vaccination as a precaution against smallpox.

Tinea Favosa, or favus, is a contagious and a very stubborn disease of the skin, caused by the fungus Achorion Schoenleinii. It produces yellowish crusts about the hairs of the scalp and other parts of the body, and it destroys the hair. It attacks also the finger-nails and the skin that is without hair. In the later stages of the disease there is a foul odour. It is one of the most difficult of the scalp-diseases to cure; months and sometimes years are required to get rid of it.

A child with tinea should be kept away from school; and his desk and what he touches should be washed with the bichloride of mercury solution. Burn his books and papers.