CHLOROFORMUM. 143 



with Slaked Lime and Calcium Chloride. (1) 2C 2 H 6 + -f- 

 Cli, = 2C,HC1 3 (chloral) + 6HC1 + 2H 2 0. (2) 2C.,HC1 3 + 

 Ca2HO = 2CHCL, 4- Ca2CH0 2 (formate of lime). 



Characters. A limpid, colourless, heavy, volatile liquid, of 

 an agreeable ethereal odour and sweet taste. Solubility, 10 in 

 7 of spirit ; 1 in 200 of water ; freely in olive oil and turpen- 

 tine. Sp. gr., 1-49. 



Impurities. Hydrocarbons ; detected by green colour with 

 sulphuric acid. Non- volatile compounds ; detected by residue 

 and unpleasant odour after evaporation. Alcohol ; detected by 

 opalescence when dropped into water. 



Dose. 3 to 10 min. 



Preparations. 



1. Aqua Chloroformi. 1 in 200 of Water. Dose, 

 \ to 2 fl.oz. 



2. Linimentum Chloroform.!. 1, with 1 of Camphor 

 Liniment. 



3. Spiritus Chloroformi." Chloric Ether." 1 to 

 19 of spirit. Dose, 10 to 60 min. 



4. Tinctura Chloroformi Composita. 2: Spirit, 

 8; Compound Tincture of Cardamoms, 10. Dose, 20 

 to 60 min. 



ACTION AND USES. 

 1. IMMEDIATE LOCAL ACTION AND TJSES. 



Externally applied, and allowed to evaporate, chloroform 

 causes a sense of coldness, and depresses the terminations 

 of the sensory nerves of the part, thus reducing sensibility or 

 removing pain. If, on the contrary, the vapour be confined, or 

 the chloroform rubbed into the skin, it acts as an irritant, 

 causing redness and even vesication, with a sense of heat and 

 pain, followed by anaesthesia of the part. A similar effect is 

 produced on all exposed mucous membranes. As a local anaes- 

 thetic, chloroform may be applied on lint, covered closely with 

 a wine-glass (e.g. in temporal headache) ; or in the form of 

 liniment with various combinations of belladonna and other 

 anodynes, which are used for the relief of lumbago, neuralgia, 

 etc. The student must understand, however, that the local 

 anodyne effect of chloroform bears a very inferior relation to 

 its rapid and powerful action as a general anaesthetic. 



Internal/!/. When it is given by the mouth, chloroform 

 produces an intensely hot, sweet taste, which renders it useful 



