Clafs II. i. 6. 7. OF SENSATION. 147 



oxygen. 1f6s I hope future experiments will confirm, and 

 that the pneumatic medicine will alleviate the evils of mankind 

 in many other, as well as in this moil fatal malady. 



M. M. Firfl, the refpiration of air lowered by an additional 

 quantity of azote, or mixed with fome proportion of hydrogen, 

 or of carbonic acid air, may be tried ; as described in a late pub- 

 lication of Dr. Beddoes o> the medicinal ufe of factitious airs, 

 Johnfon, London. Or lailly, by breathing a mixUire of one- 

 tenth part of hydrocarbonate mixed with common air, according. 

 to the difcovery of Mr. Watt, which has a double advantage in 

 thefe cafes, of diluting the oxygen of the atmofpheric air, and 

 inducing ficknefs, which increafes pulmonary abforption, as 

 mentioned below. An atmofphere diluted with fixed air (car- 

 bonic acid) might be readily procured by fetting tubs of new 

 wort, or fermenting beer, in the parlour and lodging-room of the 

 patient. For it is not acids floating in the air, but the oxygen 

 or acidifying principle, which injures or enlarges pulmonary ul- 

 cers by combining with the purulent matter. 



Another eafy method of adding carbonic acid gas to the air 

 of a room, would be by means of an apparatus invented by Mr. 

 Watt, and fold by Bolton and Watt, at Birmingham, as defcri- 

 becl in Dr. Beddoes' Treatife on Pneumatic Medicine. John- 

 fon, London. It confifts of an iron pot, with an arm projecting, 

 and a method of letting water drop by flow degrees on chalk, 

 -which is to be put' into the iron pot, and expofed to a moderate 

 degree of heat over a common fire. By occafionally adding more 

 and more chalk, carbonic acid gas might be carried through a 

 tin pipe from the arm of the iron pot to any part of the 

 room near the patient, or from an adjoining room. In the fame 

 manner a difFuiion of folution of flowers of zinc might be pro- 

 duced and breathed by the patient, and would be likely much to 

 contribute to the healing of pulmonary ulcers ; as obferved by 

 Mr. Watt. See the treatife above mentioned. 



Breathing over the rapour of cauftic volatile alkali might eaflly 

 be managed for many hours in a day ; which might neutralize 

 the acid poifon formed on pulmonary ulcers by the contact of 

 oxygen, and thus prevent its deleterious quality, as other acids 

 become lefs cauftic, when they are formed into neutral falts with 

 alkalis. The volatile fait (hould be put into a tin canifter, with 

 two pipes like horns from the top of it, one to fuck the air from, 

 and the other to admit it. 



Secondly, the external ulcers in fcrofulous habits are pale and 

 flabby, and naturally difmclined to heal, the depofition of fluids 

 in them being greater than the abforption ; thefe ulcers have 

 their appearance immediately changed by the external application 



of 



