Some cases of chronic consumption pass in a few months through the various stages from the deposit of the first tubercle to a fatal termination. The progress of the disease is determined largely by the nature of the tubercular matter at the time it is deposited. The variety of matter which has been partially vitalized commonly exists in small quantity, has a strong tendency to maintain its semi-organized condition unchanged by time, and rarely causes inflammation. A small or moderate quantity of this sort of tubercle exists in the lungs of many persons, in whom it produces no tangible symptoms, and who are therefore quite unconscious of its presence; and even when it does exist in sufficient quantity to develop the symptoms of lung disorder, the progress of the disease is slow, often continuing for many years. It constitutes a variety of consumption which is specially amenable to proper treatment. On the other hand, the soft, yellow, cheesy, tubercular matter, which is totally destitute of any vitality, is too often deposited in large quantities, acts on the adjacent lung tissue as an active irritant, causes inflammation, undergoes softening, forms cavities, defies treatment, and rapidly hurries the sufferers to a premature grave. These facts, taken in connection with the immunity from lung diseases enjoyed by those whose respiratory capacity is well developed and properly used, as well as the beneficial effects that are promptly secured in the favorable varieties of consumption by any important increase in the vital volume, I believe fully justify the statement that _tubercles are the results of defective nutrition directly traceable to inadequate respiratory capacity_, either congenital or acquired--in other words, tubercles are composed of particles of food which have failed to acquire sufficient life while undergoing the vital processes, because the person in whom they occur habitually breathed too little fresh air. Persons who possess what is called the scrofulous constitution are specially liable to the occurrence of tubercular matter when their respiration is defective, or they are exposed to any other influences that favor its development in the organism. But habitually defective respiration, or the breathing of an atmosphere containing too little oxygen, which practically amounts to the same thing, has a very powerful tendency in the same direction, in persons who are apparently as free from scrofulous taint as any human being can be. THE VALUE OF COD-LIVER OIL IN THE PREVENTION OF CONSUMPTION.