There is another class whose highest aim in life is physical labor. This class do not exercise the mind. Their muscles are exercised, while their brains are robbed of intellectual strength. . . . This class fall more rapidly if attacked by disease, because the system is not vitalized by the electrical force of the brain to resist disease. That which brings sickness of body and mind to nearly all, is dissatisfied feelings and discontented repinings.
Nothing is so fruitful a cause of disease as depression, gloominess, and sadness.
This vice is laying waste the constitution of very many, and preparing them for diseases of almost every description. Filth is a breeder of disease. Stubborn fevers and violent diseases have prevailed in neighborhoods and towns that had formerly been considered healthy and some have died, while others have been left with broken constitutions to be crippled with disease for life. In many instances their own yards contained the agent of destruction, which sent forth deadly poisons into the atmosphere, to be inhaled by the family and the neighborhood. Many suffer decayed vegetable matter to remain about their premises.