The process of deglutition may be comprehended by analyzing the operation of swallowing food or saliva.
The chyle is changed by the lacteals and mesenteric glands, but the nature of this change is not, as yet, well defined or understood.
The time required for the digestion of the different articles of food might vary in other persons; and would probably vary in the same individual at different periods, as the employment, health, season, &c., exert a modifying influence.
The system is gradually developed, and all changes of food, apparel, labor, exercise, or position, should be gradual. Even a change from a bad to a good habit, on this principle, should be gradual.
The urinary organs, as well as the intestinal canal, should be frequently and regularly evacuated. Some most distressing and frequently incurable complaints are caused by false customs and false delicacy in this particular. Teachers should be particularly careful, and regard this suggestion in reference to young pupils.