It has been shown by statistics[166] that the present generation is longer lived, and that the average of life is longer, than was the case one hundred years ago. This is solely due to the fact that now-a-days we know more of hygiene than our forefathers did, although the struggle for existence and competition everywhere has certainly become more keen, with the inevitable worry and depression of mind which it so frequently brings about. This lengthened life is certainly due to more careful hygiene, especially against infectious diseases. Footnote 166: Westergaard: “Die Lehre von der Mortalität u. Morbilität,” second edition, Jena, 1901. The extended life of an individual depends always, first, on the inherited qualities of the ductless glands, and, secondly, on a sound observance of hygienic measures. To prevent old age coming on too soon, the first condition necessary is the possession of healthy ductless glands, and this will depend, as just stated, on heredity. We can exert no influence on the generations that have passed away, and must therefore direct all our attention to the generations that are to come. This can only be done by influencing the laws of marriage, and particularly by prohibiting the marriage of persons suffering from diseases that are most detrimental to the glands with internal secretions. Children of people suffering from syphilis, tuberculosis, chronic alcoholism, etc., are, as we have seen, born with congenital atrophy of the thyroid gland, and are especially apt to acquire all infectious diseases, such as tuberculosis, with the greatest facility. The Bible is literally true when it says that the sins of the fathers are visited even unto the third generation. Thus we can influence the baby even before it is born; let us then consider what we can do after its birth to prevent premature old age and to secure for it a prolonged existence. The mother of the future child must carefully avoid anything that may prove fatal to the fœtus or influence its nutrition. It is a well demonstrated fact that different kinds of harmful products, i.e., drugs and probably also stimulants like alcohol, coffee, etc., can be conveyed to the fœtus. A pregnant woman must, therefore, most strictly observe all the rules of hygiene, and especially abstain from the use of drugs which (as for instance, iodine, the bromides, etc.) can also take effect on the fœtus and prove detrimental; emotions must especially be avoided.