I prescribed for him inhalations of oxygen in the proportion of 12 pints to 60 of air, and he took these twice in the week for five weeks; after each one he expressed himself in much the same manner as the last patient, was conscious of a general feeling of renewed health, of a greater power of breathing, and of facility of expectoration; great improvement took place in his condition, and I think it must be credited principally to the gas; for, although I ordered him 10 to 20 drops of tinct. lobeliæ at night-time, and later on tinct. fer. acetatis and frictions with the linim. tereb. acet., yet it is to be borne in mind that he had previously had a fair trial of expectorants, tonics, and even change of air, without anything like equivalent relief. CASE III. _Phthisis pulmonalis._—Mrs. W——, æt. 31, who had lost her father and sisters of consumption, consulted me in Dec. 1867. For the last six months had had cough, for the last three had emaciated, and at this time had the prostration, night sweats, diarrhœa, and hectic of the third stage of phthisis; hæmoptysis had occurred several times: the expectoration was generally purulent. There were violent pains, especially over left chest, and examination revealed a fine crepitus at apex of left lung. The patient was treated with ordinary medicines, and improved gradually. Opium in the form of an atomized spray was found to be the best medicine for relieving cough, and procuring sleep; tincture of steel and carbolic acid used in the same manner relieved, to a certain extent, the profuse expectoration; and although the case became complicated with a peri-uterine hæmatocele, in February 1868 she rallied from this also. It was July 1868 before she could walk as far as my house. Her principal symptoms then were debility, pains in the chest, cough, and copious muco-purulent sputum. At this time she began inhalations of oxygen in the proportion of 6 pints to 60 of air, increasing by degrees to 12 pints. She took eight inhalations at intervals of two days, and then found the above symptoms so much relieved as to be able to omit all treatment for a time. She herself attributed great benefit to the gas, and was taking no other special medicine at the time. Since then she has borne fairly well the cares of a large family. She has gained flesh, and though there is still a frequent cough, and sputum, and a mucous râle about the left apex (I examined the chest two days ago), the progress of the disease is arrested for a time at least.