COAGULATES ALBUMIN AND DESTROYS ORGANISMS 409 



According to Martindale, the following commercial 

 varieties are in general use : (a) Absolute phenol ; (b) 

 Carbolic acid, in crystals and in liquid, containing 10 per 

 cent, of added water : the crystals are soluble in fourteen 

 parts of water ; (c) No. 2 carbolic acid, also in crystals 

 and in liquid, soluble in eighteen parts of water ; (d) No. 4 

 carbolic acid, a pale straw-coloured liquid, containing 

 about 10 per cent, of phenol, and nearly 90 per cent, of 

 cresols ; (e) No. 5 carbolic acid, a dark-coloured liquid of 

 uncertain strength. Carbolic disinfectant powder contains 

 15 per cent, of phenols mixed with a dry powdered earth. 



The B.P. acidum carbolicum liquefactum, or phenol to 

 which distilled water has been added in the proportion of 

 ten parts of water to one hundred of phenol, is a colourless 

 or slightly pink liquid, with the taste, odour, and properties 

 of the pure acid. The empyreumatic red-brown liquid 

 commercial acid contains the uncrystalhsable, acrid methyl- 

 phenol or cresol (C 6 H 4 .(OH).CH 3 ). Calvert's carbolic 

 powders consist of 20 to 30 per cent, of carbolic acid, in- 

 corporated with refuse from the alum works. M'Dougall's 

 disinfecting powders contain about 33 per cent, of calcium 

 carbolate and 59 per cent, of magnesium sulphite. A mixture 

 of carbolic acid and bleaching powder has been patented. 

 Blast furnace residual oils consisting of 20 to 35 per cent, 

 of phenoloids, soluble in caustic soda, resemble wood-tar 

 products, and are used for preserving timber. 



ACTIONS AND USES. Carbolic acid belongs to the benzol 

 or aromatic series of carbon compounds, which are notable 

 for their antiseptic and antipyretic properties (p. 394). 

 It is a general protoplasmic poison, and closely resembles 

 creosote and creolin. Large doses are irritant and narcotic 

 poisons. It is used as an antiseptic, antiparasitic, occasion- 

 ally as a local anaesthetic, and also as a caustic. It is 

 administered in various contagious diseases, with a view to 

 prevent or arrest the development of micro-organisms. It 

 is employed as a disinfectant. 



GENERAL ACTIONS. It coagulates albumin and destroys 

 micro-organisms. It is not nearly so active as corrosive 

 sublimate, chlorine, iodine, or sulphurous acid in arresting 

 the action of ptyalin, pepsin, diastase, and other organic 



