=Heart trouble.=--Where this exists in middle life the individuals should guard against sudden emotions or over-exercise. Occasionally an old man is found dead in his bed. The explanation given to the public is heart failure or apoplexy. This was the general cause. In many cases, the immediate occasion of the sudden death was the stress and strain of sexual excitement on the heart or the brain. Again, sometimes we read of an old man being found dead in a “scarlet” home. In such cases, we know that while the real cause was apoplexy or heart failure, that the immediate cause was sexual excitement. =Genito-uninary diseases.=--Many diseases connected with the urinary and genital organs, due to gonorrhea contracted in youth, may appear in the man of middle life or old age. The disease regarded by the thoughtless youth as a trifle, is now regarded by the old man as serious. Should kidney trouble, gravel in the bladder, inflammation or enlargement of the prostate gland occur, a competent resident physician should be consulted. =Final word.=--To the young man this chapter is a faithful flagman; to the man of middle age it demands an arrest of thought, serious reflection and a manly continence; to the old worn-out roué, engulfed in the maelstrom of lust, a last “life-line” is thrown; to the well-preserved old man it will inspire a pleasant reminiscence of a pure youth, a temperate manhood, a conservative of energy in middle life, and it will add a deep sense of gratitude to the many joys of a glorious old age. CHAPTER LIV PRACTICAL QUESTIONS ANSWERED =What is the primary purpose of marriage?=--While there are several subordinate reasons for marriage, the one paramount reason is that of having and rearing a family. The only admissible reason for not having children is positive incapacity or mental and physical unfitness. =How many children should there be to a family?=--The number should vary according to circumstances. Every child has an incontrovertible right to be well born and to be well cared for after he is born. It is far better to have three to six children, who have good heredity and who are properly cared for and trained, than to have ten or twelve unfortunately born and largely neglected. Where the parents are both strong and healthy and are able to support them, a large family is commendable. =Is it wrong purposely to limit the size of the family?=--If no laws are violated and the limitation is made to safeguard the wife’s health and the best interests of the children, there can be no wrong done. =Does nature use any safeguards to the wife’s health and the right of children?=--She does. The woman is sterile before puberty, after the change of life, in most cases during the period while nursing a child, and a few days between the menses. =At what periods during the month is a wife most likely to become a mother?=--Just before or after the menses.