DISINFECTION IN PRACTICE. 35 



Salicylic acid has also been applied to vats in the form of a 

 dilute alcoholic solution, which is painted on to the surface, 

 allowed to react for some time, and then washed off with an 

 alkaline liquor, and finally with water. 



Amongst weaker antiseptics, lime and soda may be men- 

 tioned. Milk of lime, freshly prepared, forms an excellent 

 disinfectant for walls and ceilings, but as soon as the lime has 

 absorbed carbon dioxide from the air it ceases to have any 

 value. Soda, in the form of a 5 to 10 per cent, solution in 

 warm water, is an excellent reagent for dissolving slime from 

 connecting pipes, etc. It must, however, be very thoroughly 

 removed by washing first with warm, and then with cold 

 water. A very dilute soda solution (0-1 to 0-3 kilogramme per 

 hectolitre of water) is of value in swilling new chips. Soda 

 is not well adapted for disinfecting fermenting vats, as it 

 imparts a rough surface to the wood. 



One of the most important disinfectants throughout the 

 fermenting plant is steam, if care be taken that every part of 

 the vessel to be treated is exposed to its action. Connecting 

 pipes may be sterilised by steam if they do not exceed a certain 

 length. 



In distilleries, sulphuric acid is used as a disinfectant in 

 the mash to inhibit the growth of foreign bacteria, and to 

 restrict that of yeast. Its application must, however, be 

 kept within certain limits, as the yeast would otherwise be 

 damaged. According to Hayduck, 0-024 per cent, can be 

 used, and even 0-05 per cent, does not appear to prevent the 

 development of yeast. 



Ozone has found application, in particular for disin- 

 fecting water. In order to bring the gas into close contact 

 with water, the latter is sprayed over a fine-grained material, 

 where it comes in contact with a stream of ozone prepared 

 by means of a high tension electric current, discharged from 

 two electrodes of special construction. It has proved possible 

 by this means to kill a very large proportion of the organisms 

 in water (see the researches of Calmette, Schiider, and Pros- 

 kauer, Ohlmiiller, etc.). 



Hydrogen peroxide has also been applied to disinfecting 

 water, and preserving milk by Budde's process, which consists 



