On the curative effects of baths and waters : being a handbook to the spas of Europe / Including a chapter on the treatment of phthisis by baths and climate, by Rohden. An abridged translation, with notes, ed. by Hermann Weber.

Julius (Arzt) Braun

Date:: 1875

Credit: On the curative effects of baths and waters : being a handbook to the spas of Europe / Including a chapter on the treatment of phthisis by baths and climate, by Rohden. An abridged translation, with notes, ed. by Hermann Weber. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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$dryness of the air, its purity and freedom from miasma, the motion of the air, the abundance of ozone, and other matters. AVe cannot make up our mind to believe in zones of consumption and of immunity at various eleva- tions. [Our views on this subject, expressed already in the first edition, have since been confirmed by some of the best practitioners, and especially also in a purely physical point of view by the valuable researches of Tyndall in his classical work on Heat a Mode of Motion, and Frank- land 'On Combustion in Rarefied Air' {Proceedings of the Royal Institution, vol. iii. p. 331, 1862).] Tyndall and Frankland burnt six stearine candles at Physical Chamouni, and determined the loss of weight that had c?nfil™a; . ° tion of the taken place in them withm a certain time. On Mont above Blanc, therefore, about 12,000 feet higher, they repeated character- this experiment in a tent, which perfectly sheltered the Tyndall candles from the action of the wind, and observed, first, ^ , ' ' Frank- that the brightness of the flame above was much dim- land. inished, but that, secondly, nevertheless, the loss of weight in the candles was fully equal on Mont Blanc and at Chamouni. The energy of combustion on Mont Blanc was, there- fore, the same as below. The diminished power of illumination could only be ascribed to the greater mobility of the air at so great a height, and its much diminished density; the small particles of oxygen could penetrate with comparative ease into the interior of the flame, thus destroying its light, and making atonement for the small- ness of their number by the promptness of their action. Frankland afterwards made a series of experiments on combustion in artificially rarified air, and found that even the natural oscillations of atmospheric pressure cause a considerable variation in the amount of light emitted by gas flames; that, for instance, the combustion of an amount of gas which would give a light equal to 100 candles, when the barometer stands at 31 inches, would afford a light equal to only 84-4 candles if the barometer fell to 28 inches; and that each diminution of mercurial pressure equal to one inch corresponds to a decrease of$