Lectures on the compressed air bath and its uses in the treatment of disease / by C. Theodore Williams.

  • Charles Theodore Williams
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: Lectures on the compressed air bath and its uses in the treatment of disease / by C. Theodore Williams. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    structecl one, at great expense, in the new building; an example which, we trust, will be soon followed elsewhere. The construction of these air-baths varies considerably ; the size de- pending on the number of patients to be accommodated, but the following are the necessary elements. 1. A circular or ovoid iron clMmhcr,mviQ\\. resembling an engine-boiler in appearance, constructed in wrought-iron, at least -rVths of an inch thick, strengthened by girders and ribs of iron, provided with windows of thick plate-glass, and a stout door not larger than sufficient to admit one person at a time. Both windows and doors must fit closely enough to be air-tight, though, as a rule, the centrifugal pressure of the air contained in the chamber renders this easy. The chamber is furnished with the foUomng: (1) an inlet pipe for the supply of fresh air ; (2) an outlet pipe for the escape of vitiated air, and for the reduction of pressure ; (3) an air-tight cupboard, through which food and drink can be passed to the inmates ; (4) other outlets, one in the form of a whistle as an alarm signal in case of bad symptoms, and another with a safety-valve attached to prevent the pressure being excessive. The thickness of the wall depends on the amount of pres- sure to be used. Athickness of yVths of an inch sheet-iron easily sustains a pressure of 10 lbs. on the square inch, the amount most generally employed. The circular form of chamber, with an arched roof, is the one best calculated to resist pressure from within, and has, therefore, been adopted in this hospital. At St. Petersburg, one bath, consisting of two chamberSjis constructed of stone, and fitted mth double doors, after the fashion of the previously mentioned air-tight cupboard, allowing entrance and exit without alteration of the air-pressure with- in. There is also a water closet, and patients may, if required, spend several days in these two chambers. At Reichenhall, there is a large iron chamber holding nine persons ; and in one of the Paris chambers six or seven may be treated at once ; while at Dr. Fontaine's establish- ment each chamber or cloche can only hold two patients. Our bath measures 10 feet in diameter and 8 feet in height, and is constructed to accommodate four persons. 2. Apparatus for compressing the air. This is generally done by a steam-engine; the one used at this hospital being of 8 horse-power. AtM. Fontaine's bath, hydraulic power is used, the ordinary water-supply pressure of the City of Paris being turned to account to work a very ingenious hydraulic pump, which compresses the air without materially raising its temperature. This method has some advant»ges, for the air escapes the chance of being heated and rendered unpleasant by con' tact with the boilers ; but by using steam, the pressure can be more quickly increased and steadly maintained. 3. A central reservoir, to receive the compressed air, from which it can be dravm off, at will, into the separate chambers. This is the case at Reichenhall, where three baths are connected with a large anti- chamber, into which the air is pumped ; and certainly the supply is likely to be more steady and the current more even, the puffs arising from each descent of the piston not being felt in the chamber itself. In most establishments the air is pumped directly into the bath, the supply pipe entering near the lloor. In many, as at Johannisberg, Zmich, and Berlin, the pump is arranged to rarefy, as well as to condense the air, and this is done by a modification of the valves, or rather by reversing their positions. It is much to be regretted that some arrangement of this sort was not made here, but the initial cost, already very great, was an obstacle. A receiver for filtering the air from the dust and mechanical im- purity is often inserted between the compressor and the air-chamber. It generally consists of a small cylinder or box containing layers of cotton-wool, through which the inlet-pipe passes immediately before