Although some observations have been made on this topic (pages 8 and 9), the remarkable development the method has undergone, and the absorbed attention given to the whole subject by the medical profession and the public, seem to require that some additional information be laid before our readers.

Rectal injections of gas, as now employed, we owe to Bergeon, of Lyons, France. It is a curious fact, however, that the method is a mere revival of a practice carried on about a century ago. Fallen into complete oblivion, the practice has been revived by a set of circumstances rather accidental than designed. Rectal injections are among the measures utilized at medicinal springs to procure the maximum effects from the waters, especially of those, like the sulphurous, that are disagreeable to the sense of taste. It was ascertained that the gases contained in these waters—carbonic-acid and sulphydric-acid gases—are the constituents that accomplish the good effects observed in cases of phthisis, and hence the next step consisted in the application of the gases themselves. The experimental observations of Bernard were then recalled, and also his explanation of the remarkable fact that these gases thrown into the rectum escape by the lungs, and do not therefore reach the cerebro-spinal centers. Further historical researches have brought to light the observations made toward the close of the eighteenth century, and every point almost is found to be completely anticipated. Priestley, the discoverer, and Bed-does and Percival, the clinicians, are thus disclosed to us as having used the same gases, by the same method, and for the same disease. Dr. Bergeon has invented a useful contrivance for making, washing, storing up, and injecting the gases, and in an incredibly short time his method and apparatus have been employed in all civilized countries.

It need hardly be formally asserted that improvements, or, at least, modifications in the method, have been proposed. The inhalation of the same gases has been substituted for the injection, by Dr. Dupont, of Lyons, and with manifest advantage. The sedative effects of carbonic-acid gas, and the germicide action of sulphureted hydrogen, are obtained directly by inhalation, and without the need of apparatus. There is, however, now, a material having active germicide powers, which is applied by inhalation with entire facility. We refer to the combination of gases, liquefied, known as " Pictet liquid." It consists of sulphurous-acid and carbonic-acid gases, liquefied by a pressure of three atmospheres, and stored in siphon bottles. When the valve of the bottle is opened the gases escape, and so intense is the cold caused by the rapid evaporation that a part of the carbonic anhydride is frozen into snow. Pictet liquid is a powerful germicide, and hence its utility in affections of the broncho-pulmonary tract, and to prevent the development—the pullulation—of the bacillus tuberculosis. If the reader will refer to the article on sulphurous acid, he will find there some observations on the powers of this substance as a remedy in tuberculosis, and on the comparative safety of its inhalation.

So powerful a preparation as the Pictet liquid must be inhaled with care and discretion, but, as pyridine is inhaled, this liquid can be. A closet, or room of small dimensions, which can be closed, is selected; all carpets, hangings, bedding, and furniture, except a small table and chair, are removed; the slightest pressure on the valve permits a little gas to escape, and diffusion through the air of the room then occurs. As, indeed, only the patient can judge accurately of the effect produced, he should be instructed to permit the gas to escape in very minute quantity until the amount desired is obtained. A peculiar brassy taste, a slight sense of constriction of the throat, a little cough, and a faint feeling of oppression, are the effects to be obtained and to be kept up for an hour or two at each sitting, twice or three times a day. If begun with caution, and conducted with discretion, the very best results may be expected.

Sufficient experience has now been had to enable a judgment to be formed of the real value of gas enemata in the treatment of pulmonary diseases. There are, and have been from the first, several embarrassing considerations in the way of correct conclusions. The novelty of the expedient, the high claims put forth, the reported cures, and sudden enthusiasm, inflamed alike the imaginations of patient and physician, and a sober estimate of the actual value of gas-injections was well-nigh impossible. Thus much may be maintained as true, however—many patients are quickly benefited, cough, expectoration, fever, and sweats subsiding, while the appetite improves, and the general condition grows rapidly better; but it is found presently that the bacillus does not disappear, and that the improvement is more apparent than real, is not maintained, and that the continued use of gas-injections becomes irksome, at last impossible. In not a few instances the practice can not be carried out because of the local irritation; and there are many phthisical subjects not amenable to the method at all, or have a natural inaptitude that admits of no training. There appears to be a growing conviction that those phthisical subjects who have experienced much benefit from the treatment owed this result to the influences so strongly affecting the imagination of both patient and practitioner.

Various examples of asthma, of emphysema, and of chronic bronchitis have been reported cured, but the fallacy underlying these statements is only too obvious. Spasmodic asthma—the neurosis— it is probable, can be cured, and a single gas-injection might suffice; but the conditions are greatly different in the other maladies, and, although very striking improvement may be witnessed, cures do not necessarily follow, nor, indeed, have they been effected. After a candid survey of the whole subject, the author finds himself in this attitude—that the inhalation of gases is a more rational, effective, and convenient method of treating pulmonary diseases than by rectal injections.

Besides the gases referred to in this section there are certain vapor-izable liquids and solids that are utilized in the treatment of pulmonary affections by the method of inhalation that will be considered elsewhere in this work. Under their respective heads observations on such vaporizable liquids as pyridine, carbon sulphide, ethyl-iodide, and ethyl-bromide will be found, and the attention of the reader is therefore directed to them. Such vaporizable solids as iodine and iodoform are also available for the method of inhalation, but they require a special arrangement for converting the solid into vapor by means of heat. Various special contrivances exist for producing effects of a similar kind, when chloride of ammonium is formed by the union of the vapors composing it.

Referred to, for gas injections:

Beddoes, Dr. Quoted by Dupont.

Bergeon, Dr. Bul. Gén. de Thérap. Various articles during 1886 and 1887.

Dujardin-Beaumetz. Bul. Gén. de Thérap. November, 1886.

Dupont, Dr. Maurice. Bul. Gén. de Thérap. January 15,1887.

Durand-Fardel, Dr. Quoted

Minot, Dr. Francis. The Medical Record for 1887.

Paul, Dr. C. Apparatus for Gas Injections.

Percival, Dr. On Fixed Air. 1768

Priestley, Dr. Experiences with Different Kinds of Fixed Air. 1774.