The doctor told your mother not to take anything from the room until it had been disinfected. But you do not consider Towser, your dog, and Tabby, your cat, "anything," so you persuade your mother to let them come in, and you have a good play with them. You let them rub against your face and romp on your bed, and do everything that pet dogs and cats like to do, and in the meantime their fur is getting full of diphtheria germs. Then Towser and Tabby run out-of-doors and play with the boys and girls of the neighborhood. Soon the parents are wondering why the health officers do not stop the spread of the disease. No dog or cat should ever be permitted to come into a house where there is a contagious disease. These are not all the ways in which people disobey the orders of the health officer and of the doctor, but these are enough to show you that it is a very important thing to do just what they tell you. It is not always easy to follow all these rules, but it is far better to follow these, and many more, than to have to think that you have caused the death of either a friend or a stranger. =Questions.= 1. How does the poison of diphtheria get into the system? 2. Where does the diphtheria germ come from? 3. What is quarantine? 4. What is the danger in breaking quarantine? 5. Why is quarantine continued after you feel well? 6. How does it happen that some cases of diphtheria are not quarantined? 7. What is a diphtheria culture? 8. What rules should you observe while in quarantine? 9. Tell some of the ways by which quarantine is broken. 10. How do pet dogs and cats sometimes get disease germs? =Remember.= 1. The germs that cause diphtheria always come from some person or animal that carries diphtheria germs. 2. Diphtheria is always caused by the diphtheria germ, and the diphtheria germ cannot cause any other disease. 3. People are quarantined to prevent other people from getting the disease. 4. If there is diphtheria in your neighborhood, and your throat becomes sore, have the doctor examine it. 5. Every person who has been staying in a house where there is a case of diphtheria should have his throat examined to make sure he is not carrying germs. 6. Never play with dogs or cats when you have a contagious disease. 7. People who do not obey quarantine regulations cause a great deal of suffering and many deaths. CHAPTER XXIV THE CURE OF DIPHTHERIA [Sidenote: Nature of diphtheria poison] The germs of diphtheria do not get into the blood through the skin, but grow on the surface of the mucous membrane (skin of the throat), and there produce a poison that gets into the blood through this membrane. It is this poison that makes you sick, and it is called a _toxin_. You already know that when people have diphtheria, they are sometimes very sick and sometimes only slightly sick, and that the germ can live in some throats without causing any ill effects whatever. [Sidenote: How diphtheria toxin is fought]