BACTERIOLOGY. 



opening of the inner tube, which is carried down 

 with it, is obstructed by the mercury. 



Meyer's Thermo-Regulator is represented in 

 Fig. 23. No. I. shows the construction of the 



FIG. 23. MEYER'S THERMO-REGULATOR. 



regulator ; its inner tube terminates in an oblique 

 opening, and is also provided with a minute 

 lateral aperture, which prevents the complete 

 shutting off of the gas supply. No. II. illustrates 



