The exhalations from low, moist, and marshy localities, from the offensive cesspools, water-closets, sinks, sewers, and the decomposition of animal and vegetable substances, from the refuse or garbage which so often befouls the sidewalks and gutters of streets, are all effective, predisposing causes, that directly facilitate the production of the cholera. Whatever tends to depress the vital powers, impair normal action, or relax in any degree the tone of the nervous system, favors the operation of the final cause. So, too, the low, underground, damp, unventilated apartments, the crowded and uncleanly tenement houses, in which multitudes of the poorer class live, in a confined, foul, and noisome atmosphere, not only favor, but actually invite, the active operation of the infecting agent. Habits of intemperance, profligacy, impurity, and late hours, have a powerful influence to depress and prepare the system for an invasion of the disease in its most malignant form. In a neighborhood of this description, when the cholera in 1832 was raging in the adjacent city, from which it was separated by a very small creek, the uncleanly multitude escaped entirely, not a case occurring there at that time; but when, after an interval of several weeks, all danger seemed to have passed, and the people were rejoicing and congratulating themselves on their good fortune, the fearful disease suddenly appeared in their midst with greatly intensified effect, and in a very few days swept the place so clean that few were left to tell the sad story of its ravages. There are some other predisposing causes of no inconsiderable influence, which not only favor the operation of the infecting agent in the production of the disease, but even awaken its latent power, and stimulate its activity and development in the system, once exposed to its invasion. Among these, excessive fear of an attack, great anxiety and depression of mind, constitutional debility, deranged condition of the digestive organs, accompanied with a relaxed state of the bowels, exhaustion arising from fatigue or disease, semi-starvation and unwholesome diet, neglect of personal and domestic cleanliness, irregular habits, and excesses of every description, are all direct incentives and stimulating agents in the production of the cholera. Any one of these may be sufficient to induce an attack; but when a number unite and act conjointly the danger is vastly greater, as the infecting agent or disease-poison becomes thereby more intensified.