The smoke palls of our industrial centers exert both a direct and indirect influence upon the human organism. The direct influence is due to the immediate contact of the smoke-contaminated and poison-laden air with the skin, mucous membranes and sense organs of the body. The indirect effects are traceable to the various meteorological states which are due to smoke products in the atmosphere, and which in turn directly influence the body. Frequently, possibly always, the smoke conditions and the state of the atmosphere are so inextricably mixed that the biological effects must be ascribed to the joint action of both factors. Only in a controlled experiment would it be possible absolutely to segregate, and thus separately to measure, the effects of the smoke and meteorological factors of weather states. This has not yet been attempted. The mental effects due to atmospheric smoke and its related weather states are likewise both direct and indirect. The indirect effects are due to the influences exerted by smoke clouds and smoke-produced weather states on the physiological organism--on health, well-being, energy, freshness, potential reserve, sensori-motor efficiency--and to the influences thus directly exerted by the changed bodily states on the mind: on mental tension, balance, inhibition, impulse, inclination, feeling, emotion, thought, and conduct. On the other hand, the direct mental effects are traceable to the immediate influences, whether conscious or unconscious, exerted on the individual’s mental action by his own experiences--by the thoughts, feelings and impulses which have been excited in him by various bodily states, sensations and perceptions produced by cloud and weather conditions--or which have been directly produced by processes of association and habit formation, the latter of which have themselves been initiated by thoughts or responses occasioned, in the first instance, by the physiological effects of external influences. The action of the mind itself does have a determining influence upon its own subsequent attitudes, beliefs, propensities and habits. It is important that these direct effects of the mind’s own action upon its subsequent behavior be recognized, for much of the mental gloom and depression occasioned by dismal cosmic influences has merely been initiated by the external stimuli. Their peculiar intensity is largely due to the subject’s own introspections, to his own stream of thought. The mental influences are often more pronounced than the bodily influences, whether the mental influences arise from somatic alterations or from introspective changes. Cosmic states are, perhaps, less to be regarded as _causes_ of mental action than _factors_ which may upset the emotional balance, lessen inhibition and alter the train of thought and conduct.