REFLECTIONS ON DISEASE TREATMENT 157 
and leave the firm parts untouched. The soil is next 
packed well round the sides of the boxes to prevent any 
escape of steam. It is always advisable to remove the 
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¥ 1 
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(c) Grid. 
Fig. 41. ‘* Box and grid ” for steam sterilization. 
soil used for packing, before lifting off the box, as it is 
rarely sterilized, and is a source of contamination. It 
