8 ' 
ulating fliers of tlie valve project on the outside of the apparatus: In 
the middle of the valve a needle is welded which occupies the axis of 
the cylinder, and which, when the valve is raised, may be lodged in the 
aperture with which the stopper of the cylinder is provided. In this 
way, when the valve is raised up and the lower orifice unmasked, the 
upper orifice is closed by the needle. When, on the contrary, the valve 
closes the lower orifice, the aperture of the stopper is uncovered and 
allows the liquid to pass out. 
c. y. r. 
