METHODS OF STERILIZATION 9 



for rapid work, the Koch apparatus requiring a long time to obtain 

 the temperature of 100 C., from which moment the period of steriliza- 

 tion can be estimated. 



Messrs Lautenschlager, Berlin, have recently, at the writer's sug- 

 gestion, constructed a useful portable steam sterilizer, costing 27/- 

 (see Fig. 3), showing the apparatus with the outer cover removed, and 

 the inner lid of the steam chamber slightly raised. The outer cover 

 can also be used without the inner lid when a temperature lower than 

 100 C. is required ; a place for a thermometer being provided. 



Fig. 4 shows a section of the apparatus, P being the water 

 reservoir, and the boiling chamber being constructed similar to the 

 Arnold apparatus. A and D show the junction of the steam and 

 water chambers by means of a strong detachable telescopic joint, 

 enabling the water chamber to be cleansed, and also facilitating the 

 packing of the apparatus during transportation. The size of the 

 opening admitting the steam into the steam chamber is regulated 

 with a diaphragm fitted on the inside of the steam chamber. 



FIG. 3. 



FIG. 4. 



Bowhill's Steam Sterilizer. 



Whereas the above means of sterilization at 100 C. suffice for 

 ordinary purposes, an apparatus for sterilization by steam under 

 pressure, known as an Autoclave (see Fig. 5), is at times very useful, 



