3O BACTERIOLOGY. 



In the centre of the cylinder is a column which 

 communicates with the water chamber of the 

 cylinder, and from it pass four partitions, which 

 serve to support the test-tubes. 



In the lid are three openings, one of which com- 

 municates with the water chamber in the lid by 

 which the latter is filled, and into which a thermo- 

 meter is then fixed. In the centre an opening 

 admits a thermometer, which passes into the 

 central pipe of the cylinder ; through a third open- 

 ing a thermometer passes to the cavity of the 

 cylinder. The cylinder and cover are jacketed 

 with felt, and the apparatus is supported on iron 

 legs. 



Serum Inspissator. A shallow tin case with 

 glass cover, both case and cover jacketed with felt 



(Fig. 15). The case 

 is double walled, and 

 the water contained 

 in the interspace is 

 heated from below. 

 It is supported on 

 four legs, and the 



FIG. IS.-SERUM INSPISSATOR. two front ones move 



in grooves in the 



case, so that the latter can be placed obliquely at 

 the angle required, and secured in position by 

 screw-clamps. It is employed for coagulating 

 sterile liquid serum, and for solidifying nutrient 

 agar-agar so as to give them a sloping surface. 



