39 



Heat the linseed oil in a tared vessel of a capacity equal to 

 about four times the bulk of the ingredients, on a water bath to a 

 temperature of 70°C. Dissolve the potassium hydroxide in 10 mils 

 of water and warm to 70°C., add it to the linseed oil and mix 

 thoroughly. Then incorporate the alcohol and continue to heat the 

 mixture without stirring until a small portion is found to be solu- 

 bile in boiling water without the separation of oily drops. While 

 yet warm add the cresol and mix thoroughly, maintaining the tem- 

 perature at about 70°C., until a clear solution is produced. Finally 

 add sufficient water to make the finished product weigh 200 grams. 



Note : — The Pharmacopoeia directs that 10.8 Gm. of sodium 

 hydroxide may be substituted for the 16 Gm. of potassium hydroxide 



Remarks: — The above solution is a 50 per cent, solution of 

 cresol in an alkaline linseed oil soap. It is similar to many popular 

 and "trade-named antiseptics" such as Lysol, Creolin, etc. The 

 commercial cresol used in this preparation is a mixture of cresols. 

 It is commonly called "Cresi/lic Acid." 



Liquor Potassii Arsenitis — Solution of Potassium Arsenite. 



This is an aqueous solution which should contain Potassium 

 Arsenite corresponding in amount to not- less than 0.975 per cent, 

 nor more that 1.025 per cent, of arsenic trioxide. For practical pur- 

 poses it is a 1 per cent, solution. 



Arsenic Trioxide 1.0 Gm. 



Potassium Bicarbonate 2.0 Gm. 



Compound Tincture of Lavender 3.0 Gm. 



Distilled Water, a sufficient quantity 



to make 100.0 Gms. 



Boil the potassium bicarbonate and arsenic trioxide, in a tared 

 dish, with 10 gms. of distilled water, until a solution has been ef- 

 fected. Then add enough distilled water to make the solution weigh 

 97 gms. ; then add the Compound Tincture of Lavender. Filter 

 through paper. 



Remarks: — This preparation is commonly called "Fowler's 

 Solution." It contains 1% of Arsenic Trioxide colored with Com- 

 pound Tincture of Lavender. 



