27 Boston Medical and Surgical Journal, 1885, p. 66.

Leyden, whose theory has been mentioned elsewhere, has proposed a new treatment based upon the solubility of the Charcot crystals in chloride of sodium and carbonate of sodium. A solution of one part of these salts in one hundred parts of water should be inhaled twice daily in the form of a spray.

Oxygen has often been used in asthma, but is now seldom administered except in cases associated with great anæmia.

Sée gives the following statistics of the results of the treatment with compressed air in asthma and its secondary affections. Bertin used it in 15 cases of emphysema, all of which he cured, and in 92 cases of nervous and catarrhal asthma with emphysema, of which 67 were completely and 22 partially cured, while it was only unsuccessful in 3 cases. Of Sandahl's 77 cases of asthma with emphysema and bronchitis, 57 were much relieved, and of 14 uncomplicated cases, all were completely relieved. Compressed air may be applied either by placing the patient in a pneumatic cabinet or by means of the portable apparatus of Waldenburg. It must be remembered, however, that in the cabinet the compressed air acts upon the whole body, while in the portable apparatus only the air-passages and alveolæ are subjected to pressure; hence if the latter is used the amount of pressure must be considerably diminished. Notwithstanding the success claimed for this method of treatment, it should be used with caution, and if the case is complicated with emphysema it should either be regarded as contraindicated, or, if employed, the pneumatic cabinet should be used and not the portable apparatus. In the former, or "air-bath," the exterior pressure of the compressed air acts as an auxiliary to "the elasticity of the thorax and to the abdominal gases in" expiration, and at the same time, by compressing the vessels outside the thorax, aids the venous circulation. The same force exercised on the inner surface of the tubes tends to lessen the hyperæmia of the bronchial mucous membrane (Moeller).28 When the portable apparatus is used, expiration in rarefied air causes retraction of the thorax, and thus in a measure overcomes any tendency to emphysema. A better plan than to use either singly is to combine the two—to expire into rarefied and inspire compressed air—which may be readily accomplished with several of the improved portable apparatuses.

28 Thérapeutique locale des Maladies de l'Appareil respiratoire, Paris, 1882, p. 283.

The inhalation of sulphuretted hydrogen as practised at Eaux Bonnes, Cauterets, Aix-la-Chapelle, and other sulphur baths, is said to have cured some cases, while in many others great benefit is claimed to have been derived from its use; but allowance must be made for exaggeration in many of the reports published.

In giving the treatment of asthma no allusion has been made to Grindelia robusta and other recently-introduced remedies, partly because the writer has had no experience with them, and again where he has tried them they have given negative results.

HAY ASTHMA.