I am cleaning and reassemblying a Solex PHH 3 side draft carburetor. I am not sure what this brass part is called, but for lack of a better definition, I will call it an 'emulsion tube'. The tube is about 2 inches long, 1/4 inch diameter, has two long narrow slots about 1 inch long opposite each other lengthwise on one end of the tube. The tube does not screw in but rather is inserted into the carburetor body, held in place by friction and positioned such that the long slots extend well into the cylindrical air intake area. Apparently the incoming airstream acts upon these slots to do something but I am not sure how they are supposed to be positioned relative to the incoming airstream. Do these slots align with the incoming air stream or are they at 90 degrees to it? THANKS!