INTRODUCTION. 



21 



preferable — is poured into the funnel. Experience proves that ^o pump- 

 ing force is required to inject fluid into the intestines, the effect of gra- 

 vitation fulfilling the same purpose in a much more simple manner. As 

 the fluid from the funnel gi-avitates into the rectum, bubbles of gas escape; 

 the action of the gut, thus mildly stimulated, continues until, with the 

 repetition of the process at intervals of a quarter of an hour, the required 

 evacuation is induced, with its attendant 

 relief. Farmers and others who keep a 

 number of h orses should obtain an instru- 

 ment like the one described : made of tin, 

 it is light, cheap, and very durable. 



Disinfectants. — The particles of con- 

 tagious or infectious matter, like other 

 organic ferments, are very unstable in 

 their composition and are easily acted on 

 by various chemical agents. Such agents 

 are called Disinfectants. They act either 

 by poisoning or 

 killing the fer- 

 ment; or by ab- 

 stracting the hy- 

 drogen from noxious gases and vapors, break them up. Chlorine gas, 

 carbolic acid, and many other compounds are commonly used for these 

 purposes. 



True disinfectants act chemically by decomposing noxious gases and 

 organic matters. Such are chlorine and its compounds, sulphurous acid, 

 Condy's fluid, chloride of lime and soda, carbolic acid, etc. Their 

 action is produced by their affinity for hydrogen, which is a constituent 

 of most of the deleterious matters found in the stable. They appro- 

 priate to themselves this constituent, and by this means break up the 

 poison. Most disinfectants are also deodorizers. 



Deodorizers generally, as distinguished from disinfectants, act me- 

 chanically. They have an affinity for certain compounds floating in the 

 air, and imbibe and absorb them. Such are sawdust, powdered char- 

 coal, plaster of Paris, sulphate of iron, clean dry earth, sand, perman- 

 ganate of potassa. Deodorizers may, under some circumstances, become 

 so overcharged with noxious matters that they may of themselves volun- 

 tarily give them off. Earth, for instance, which is a most valuable 



Fig. 13. 

 Gamgee's funnel for injections. 



