3. The importance of less stimulating and exhausting methods of conducting business avocations in large towns and cities. A more full recognition of the fact, that every brain is limited to its unit of power in activity--so much and no more,--and that length of days and fulness of strength can be expected only by the judicious care and expenditure of brain-force. 4. A more full recognition of the importance to the brain of _change_ and longer periods of rest, both for adult persons when engaged in the usual avocations of life, and especially for children in relation to the hours of sleep. 5. The importance of improved sanitary conditions for all houses occupied by the poor, especially in cities, and of all shops and manufacturing establishments. The kinds of avocations followed in-doors are not likely to be much changed or lessened; indeed, I think they are likely to become even more common; that larger numbers will be engaged in such occupations in the future than in the present; but it is quite possible to realize more fully the fact that the brain requires the effects of pure air, if it is to remain in a condition of health, and that it is practicable to introduce this to all places so occupied. As will readily be perceived, the tendencies of the preceding pages have served to point toward the importance of systematic preventive measures concerning insanity. _Prevention_ is the watchword which is being signalled along the line of the medical profession, at the present time, concerning the management of disease. The importance of State Boards of Health in many of the larger States has become so generally recognized, that they are yearly appointed, and make regular reports, with more or less full accounts as to the results of observations in reference to the public health and the prevention of disease, which prove to be of the highest value. I would suggest the importance of appointing on such Boards one or more physicians who are qualified for such a position, whose special duty it shall be to ascertain and make public reports upon the prevalence of such conditions as conduce to the production of mental disease. They should be appointed by the State, so that they may have influence with school teachers and school boards. In this way they may be able to point out the dangers which lie in methods of educating and preparing the young for the duties and responsibilities of life. Such persons should be able to wisely direct in laying the broadest and most secure foundations on which to rear the fabric of vigorous mental health.