The main suffering, the "besoin de res-pirer," common to these maladies, is clearly traceable to deficient access of oxygen to the blood in the lung-capillaries, and I am satisfied that in the majority of instances relief to this suffering may be given by supplying a larger proportion of the gas. If it be objected that permanent good results are not obtained from it, the same objection may be made to many other remedies; it is still something to have a means at hand for temporary relief. Dr. John Hooper thus describes its effects in a man of fifty-five, "for many years a martyr to asthma." During a very severe paroxysm he was thought to be dying - it seemed impossible that he could rally. As a dernier ressort, oxygen was tried, the end of a glass retort containing it being applied to his mouth, though he had not power to enclose it with his lips. "The effect was wonderful and quickly manifest in increased mobility of the ribs, fuller inspiration, disappearance of lividity, and lastly in his seizing the end of the retort, and in the avidity with which he inhaled when possessing the voluntary power" (British Medical Journal, i., 1862). Details of diagnosis are not given in this instance, but paroxysms of true nervous asthma and of bronchitic asthma may both be shortened by similar inhalation. Beddoes related twenty-two cases, of which he claimed to have cured ten and relieved nine; and it seems worth while to refer to his case of "Mr. Hare, of Conduit Street, who, in 1796, after having been subject for eleven years to asthmatic attacks accompanied by indescribable suffering, and only relieved after many hours by blisters and expectorants," recovered average health under the use of the gas continued for some months (op. cit., 4th part, p. 49). M. Demarquay also witnessed excellent results, e.g., in a man aged nineteen, subject from childhood to asthmatic attacks: "they ceased, as if by magic, as soon as he began to inhale oxygen ("Essai de Pneumato-logie," p. 725).

Dr. Mackey has reported a good illustration of the value of the gas in advanced emphysema pulmonum (Practitioner, vol. ii., May, 1869). A lady, aged fifty-five, was subject to constant dyspnoea, increased by every movement, and amounting at times to partial asphyxia. She had the physical signs of the malady, together with dilated weak heart and embarrassed cir-culation, as evidenced by oedema of the face and extremities; was subject to attacks of bronchitis, but at the time of treatment the main complaint was the difficulty of breathing. She inhaled a mixture of from three to twelve pints of oxygen, with sixty of air, at intervals of three or four days, for a period of six weeks. After each dose "marked relief was experienced, which she expressed as being able to take a deep breath and get sufficient air (a feeling not known for years), as being able to move with comparative ease, feeling more buoyant and more like healthy persons should feel than she ever remembered." Expectoration was rendered more copious and facile for a day or two after the inhalation; there was no other definite effect on secretion, nor any on circulation, unless it were some palpitation during the night after a large dose. The nervous irritable states to which such patients are liable were also soothed under the treatment, which certainly effected more than ordinary medicinal agents.

It could not, however, alter the organic conditions, and cardiac death occurred suddenly, after an attack of bronchitis, in the following winter.

These illustrations seem to me sufficient to prove that oxygen might be used more often than it commonly is in such cases. According to Biedert's method, emphysema is treated by a few short sittings of respiration in compressed air, and then by expirations into an atmosphere of rarefied air, "in order to counteract anaemia by attracting blood toward the lung-tissue."

In Bronchitis, bronchial catarrh, and bronchial asthma, compressed air is used to stimulate the lung, improve its circulation, and facilitate expectoration; it seems to be useless during actual asthmatic attacks. In mitral disease it is said to be valuable, and in dyspnoea dependent on dilatation of the right heart.