are placed at the bottom of the jar, one of the usual oxygen indicators (for example, alkali^6' glucose-methylene-blue mixture) placed aloflj? with the cultures, and the jar sealed. After jj to 12 hours, according to the size of the jar an" the amount and quality of iron filings, the colour of the indicator is discharged and co1*^ plete anaerobiosis obtained. Approximately " grammes of iron fil...