A degree of vertigo may be produced by loading the stomach too rapidly and copiously after a long fast. Common food, in this instance, amounts to a strong stimulus in consequence of the state of the stomach, in which there was an unnatural want of excitement. This organ was in a state of torpor; and a stimulus which, in ordinary circumstances, would hardly have been felt, proves, in reality, highly exciting. For the same reason, objects have an unnatural luminousness when a person is suddenly brought from intense darkness to a brilliant light. II. _Double Vision._—The double vision which occurs in drunkenness may be readily accounted for by the influence of increased circulation in the brain upon the nerves of sight. In frenzy, and various fevers, the same phenomenon occurs. Every nerve is supplied with vessels; and it is conceivable that any unusual impulse of blood into the optics may so far affect that pair as to derange their actions. Whence, they convey false impressions to the brain, which is itself too much thrown off its just equilibrium to remedy, even if that under any circumstances were possible, the distorted images of the retina. The refraction of light in the tears, which are secreted more copiously than usual during intoxication, may also assist in multiplying objects to the eye. III. _Staggering and Stammering._—These symptoms are, in like manner, to be explained from the disordered state of the brain and nervous system. When the organ of sensation is affected, it is impossible that parts whose actions depend upon it can perform their functions well. The nervous fluid is probably carried to the muscles in a broken and irregular current, and the filaments which are scattered over the body are themselves directly stunned and paralyzed; hence, the insensibility to pain, and other external impressions. This insensibility extends everywhere, even to the organs of deglutition and speech. The utterance is thick and indistinct, indicating a loss of power in the lingual nerves which give action to the tongue; and the same want of energy seems to prevail in the gustatory branches which give it taste. IV. _Heat and Flushing._—These result from the strong determination of blood to the surface of the body. This reddens and tumefies the face and eyes, and excites an universal glow of heat. Blood is the cause of animal heat, and the more it is determined to any part, the greater is the quantity of caloric evolved therefrom. V. _Ringing in the Ears._—This is accounted for by the generally increased action within the head, and more particularly by the throbbing of the internal carotid arteries which run in the immediate neighbourhood of the ears.