HIPPOLYTE VARTANS. 



597 



Fig. 1. 



Circulatory apparatus. A is the aspirator by which air is sucked through the 

 " air-circulator " flasks B and C, and then through A to replace the 

 water circulating through D and E. The rate of the circulation depends 

 upon the vertical distance x' y between the level of x (the commence- 

 ment of the outlet tube) and y (the point of exit of the water from the 

 apparatus). Of the three tubes {a, b, c) passing through the cork of the 

 aspirator A, a allows air to escape in filling the bottle through b from the 

 main tank of the laboratory, while c transmits the air from the flasks B 

 and C. 



