On Disinfectants. 97 



into a sliallow earthenware vessel and mixed ■\\dtli 4 ozs. of oil of vitriol 

 and 2 ozs. of water ; the vessel containing this mixture is then placed 

 over heated cinders, the heat of which causes the acid gases to bo 

 evolved in abundance. 



Still more conveniently, and without the application of heat, nitrous 

 acid fumes may be generated by pouring ? lb. of concentrated nitric 

 acid upon 3 ozs, of copper shavings or turnings put into a tall jar or 

 basin. 



Quich Lime. — Quick lime disorganises and by degrees destroys 

 animal and vegetable matters, and at the same time absorbs products 

 of decomposition, such as sidphuretted hydi'ogen and carbonic acid. 

 It is thus at once a disinfectant and a deodorizer. It ought to have 

 been recently burnt, and may be used for disinfecting purposes, either 

 in the form of dry powder or stirred uj) with about ten times its bulk 

 of water, as milk of lime. 



In the shajie of a tliick lime-wash quick lime receives extensive appli- 

 cation as a disinfectant ; and in the form of dry powder it is a good 

 and the most practically available means for disinfecting carrion, dung, 

 and manure-heaps from cattle that have died of plague. 



Soda-ash. — Crude carbonate of soda, or soda-ash generally contains 

 some caustic soda in addition to carbonate, and as it is a cheap 

 material and its action upon organic matters similar to that of quick 

 lime, but more energetic, it deserves to be employed more extensively 

 than it is at present for disinfecting purposes. 



Soda-ash is readily soluble in water, 1 lb, of soda-ash dissolved in 

 2 gallons of warm water is a liquid which, apart from its disinfecting 

 powers, recommends itself by its excellent detergent properties for 

 removing organic filth adhering to woodwork, mangers, wooden stable 

 utensils, and all other articles which may have become soiled by 

 infected cattle. 



Quick lime is only sparingly soluble in w^ater, and for this reason 

 does not dissolve organic matters so readily as soda-ash, nor does quick 

 lime destroy them so rapidly as the caustic alkali in the soda-ash. 



Wood or peat charcoal possesses a remarkable destroying power on 

 organic substances. If dry, charcoal absorbs diiferent gases in very 

 diiferent proportions, as will be seen in the following tabular view of 

 Saussure's results : — 



Absorption of Gases hy fresldy-hunied Charcoal. 



One volume of cliarcoal absorbed — Volumes. 



Ammonia 90-0 



Hydrochloric acid 85'0 



Sulphurous acid f;5-0 



Sulphuretted hydroLreu 55-0 



Protoxide of nitrogen . . 40"0 



Carbonic acid 35-0 



Bicarburetted hydrogen 35"0 



Carbonic oxide 94 



Oxygen 9-2 



Nitrogen 7*2 



Carburetted hydrogen o*0 



Hydrogen 1"7 



VOL. TI. — S, S. H 



