When this obstruction of the circulation by uric or carbonic acid prevails throughout the body, the blood pressure is too high in the arterial blood vessels and in the interior organs, such as heart, lungs, brain, etc., and too low in the surface, the extremities and in the venous circulation. The return flow of the blood to the heart through the veins is sluggish and stagnant because the force from behind, that is, the arterial blood pressure, is obstructed by the uric acid which clogs the minute capillaries that form the connection between the arterial and the venous systems. Because of this interference with the normal circulation and distribution of the blood, uric acid produces many annoying and deleterious effects. It irritates the nerves, the mucous membranes and other tissues of the body, thus causing headaches, rheumatic pains in joints and muscles, congestion of blood in the head, flushes, dizziness, depression, fainting and even epilepsy. Other results of uric acid irritation are: inflammatory and catarrhal conditions of the bronchi, lungs, stomach, intestines, genitourinary organs; rapid pulse; palpitation of the heart; angina pectoris; etc. These colloid substances occlude the minute excretory ducts in liver, spleen, kidneys and other organs, interfering with their normal functions and causing the retention of morbid matter in the system. All these troublesome and destructive effects of uric acid poisoning may be greatly augmented by excessive accumulation of sulphuric, phosphoric and other acids, and by the formation of ptomaines and poisonous alkaloids during the metabolism of proteid substances. The entire group of symptoms caused by the excess of uric acid in the system and the resulting occlusion of the capillary blood vessels by colloid substances is called ~collemia~ [a glutinous or viscid condition of the blood]. If in such a condition as collemia the amount of uric acid in the circulation is still farther increased by the taking of uric acid-producing food and drink and the saturation point of the blood is reached, that is, if the blood becomes overcharged with the acid, a curious phenomenon may be observed: the collaemic symptoms suddenly disappear as if by magic, giving way to a feeling of physical and mental buoyancy and strength. This wonderful change has been wrought because the blood has lost its capacity for dissolving uric acid and holding it in solution and the acid has been precipitated, thrown out of the circulation and deposited in the tissues of the body. After a period of rest, that is, when no uric acid-or xanthine-producing foods have been taken for some time, say, overnight, the blood regains its alkalinity and its capacity for dissolving and carrying uric acid and begins to reabsorb it from the tissues. As a consequence, the blood becomes again saturated with uric acid and the collaemic symptoms reappear.