Nature has provided an Automatic Food Filter which, if rightly used, will prevent the introduction of any harmful substance into the stomach. * * * * * At the entrance to the throat there are certain muscular folds or convolutions, including the palate, which, when in repose, form an organ that is nothing less than a Perfect Food Filter. This filter has also automatic qualities which compel it to empty itself by the process we call "Involuntary Swallowing." Involuntary swallowing is really compulsory swallowing; unless a voluntary effort to restrain it is set up against it. The real Swallowing Impulse is so strong that it is practically compelling. The Food Filter, when rightly performing its protective function, is impervious to anything except pure water at the right temperature for admission to the stomach and to nutriment which has been properly dissolved and chemically converted by salivation (mixture with saliva) into a substance suitable for further digestion. IMPORTANCE OF MASTICATION If we masticate--submit to vigorous jaw action--everything that we take into the mouth, liquid as well as solid, until the nutritive part of it disappears into the stomach through compulsory or involuntary swallowing, and remove from the mouth all fibrous, insoluble and tasteless remainder, we will take into the body, thereby, only that which is good for the body. * * * * * The first thought that will arise in the reader's mind on perusal of the above declaration will undoubtedly be, "What! masticate milk, soups, wines, spirits, and other liquids; nonsense! That is impossible!" It is not, however, impossible, and, furthermore, it is _absolutely necessary to protection against abuse of the stomach and possible disease_. Liquid for adults, for anyone after the eruption of teeth, is an artificial and unnatural sustenance; something not taken into consideration when the human body was planned. Liquid food (drunk without mixing with saliva) is a sort of nutritive self-abuse, and the only way to avoid the ill effect is to give it the same chance to encounter saliva that the constituent ingredients would have had in a more solid state. For the importance of this see Dr. Campbell's able treatise on mastication reprinted from the London _Lancet_ in the "A.B.-Z. of OUR OWN NUTRITION." * * * * * The only things necessary to life that we are compelled to take into the body that do not excite the sense of taste are pure air and pure water. These are necessary to life, but are not what is called nutrition. They do not, alone, replace waste tissue. They do not challenge the sentinel, Taste, and hence do not require retention in the field of taste.