is very dangerous. The poisonous germs in it rise into the air, and, being inhaled by others, lead to a spread of the disease. We should keep a spittoon inside the house, and if we have to spit when out on the road we should spit where there is dry dust, so that the spittle may be absorbed into the dust and cause no harm. Doctors hold that the consumptive should spit into a spittoon with some disinfectant in it: for, even if he spits on dry ground, the germs in his spittle manage to rise and spread into the air along with the dust. But, in any case, there can be no doubt that the habit of spitting wherever we please is dirty as well as dangerous.
Some people throw where they like cooked food and other articles, which decay and render the air impure. If all such rubbish be put underground, the air would not be made impure, and good manure, too could be obtained. In fact, no kind of decaying matter should be allowed to lie exposed to the air. It is so easy for us to take this necessary precaution, if only we are earnest about it.
Now we have seen how our own bad habits render the air impure, and what we can do to keep it pure. Next we shall consider how to inhale the air.
As already mentioned in the last chapter, the air is to be inhaled through the nose, and not