624 MEDICINES. 



Iodoform, 



which is an admirable antiseptic, does not destroy bacteria ; but 

 it induces chemical changes in the poisonous materials which they 

 produce, so as to render them harmless. Unlike corrosive sub- 

 limate, and to a lesser degree, carbolic acid, iodoform has no 

 irritating effect on a wound. Iodoform requires the presence of 

 pus to cause it to become decomposed and to give off its iodine, 

 to which it owes its antiseptic property. Hence, iodoform will 

 not form a dry scab in the first instance. It can be used dry, or 

 with eucalyptus oil, in which as much iodoform has been dissolved 

 as the oil will take up. 



See p. 539. 



Ipecacuanha. 



Iron. 



SidpJiate of Iron 



should be kept in well-stoppered bottles ; for if exposed to the 

 air it will gradually become decomposed. It is a valuable tonic ; 

 although it is apt to have a constipating effect. If it upsets the 

 digestion, it should be discontinmed. 



Preparations of iron should not be employed in cases of 

 indigestion, or of diseased liver (p. 540). 



Dose, 20 to 60 grains once or twice a day, mixed in the food. 



A solution of 1 lb. to the gallon of water is an admirable dis- 

 infectant for stables. When brought into the presence of 

 ammonia and sulphuretted hydrogen, the ammonia becomes 

 fixed by being converted into the sulphate ; and the sulphuretted 

 hydrogen is decomposed by yielding up its sulphur to the iron. 



Only green crystallised sulphate of iron should be employed for 

 internal use. The impure kind will do for disinfection. 



Dialysed Iron. 



A solution of dialysed iron (^ oz.) diluted with water, to be 

 given two or three times a day, is a valuable tonic, and is not 

 liable to act injuriously on the digestion, or on the liver (when 

 affected) like sulphate of iron. 



