CHEMICAL SCIENCE. 279 



CHARCOAL RESPIRATOR. 



Dr. Stenhouse recently described to the London Society of Arts a new 

 species of respirator filled with powdered animal charcoal, to absorb and de 

 stroy any miasmata or infectious particles present in the air in the case of 

 fever and cholera hospitals, and of districts infected by ague, yellow fever, 

 and similar diseases. The respirator fitted closely to the lower portion of the 

 face, extending from the chin to within half an inch of the eyes, and pro- 

 jected about an inch on either side of the mouth. It therefore included the 

 nostrils as well as the mouth. The frame of the respirator was made of thin 

 sheet copper, but the edges were formed of lead, and were padded and lined 

 with velvet, so that it could be easily made to fit tightly to the face. The 

 powdered charcoal was kept hi its place by means of two sheets of fine wire 

 gauze, about a quarter of an inch apart. The object in view was, by filtering 

 the air through such a porous substance as animal charcoal, to intercept the 

 miasmata which might have got mixed with it. Eepeated trials with the 

 respirator had shown that certain noxious and offensive gases, such as am- 

 monia, sulphureted hydrogen, and hydrosulphate of ammonia, had been 

 rapidly oxydated and destroyed in their passage through the pores of the 

 charcoal. The author then mentioned several instances in which the bodies 

 of dead animals had been completely covered with thin layers of charcoal, 

 which entirely prevented any effluvia or odor being perceptible. He con- 

 sidered that covering a church-yard to the depth of from two to three inches 

 with coarsely-powdered charcoal, would effectually prevent any putrid exhal- 

 ations ever finding their way into the atmosphere. Charcoal, though a de- 

 odorizer or disinfecting agent, was not, as laid down by chemical works, an 

 antiseptic. On the contrary, it favored the rapid decomposition of the dead 

 bodies with which it was in contact ; so that hi the course of six or eight 

 months little was left except the bones. 



An interesting experiment illustrating the sanitary powers of charcoal has 

 been instituted at St. Bartholomew's Hospital, London, by Dr. Stenhouse. 

 An atmosphere rendered highly offensive by putrefactive decomposition going 

 on within the chamber in which it is confined, is drawn through charcoal 

 filters, by means of a rotating fan machine, and is passed into an apartment 

 adjoining. Although this air is disgustingly fetid, it flows out into the room 

 perfectly free from smell. The remarkable property which charcoal has of 

 condensing within its pores large quantities of the fetid gases is greatly in- 

 creased by a process of platinizing the charcoal. This new invention merits 

 the attention of the man of science, from the extraordinary -energy with which 

 ie acts upon the gases, and of all those persons scientific or not who are 

 interested in the public health, since it furnishes us with a new power for re- 

 moving from among us the agents of disease. 



