EXPERBIENTS WITH IONIZED AIR. 



29 



the latter being secured in any position by tlie snugly fitting screw at C. The 

 top of the spindle B is ground into the upper aperture of the body like an 

 ordinary screw valve, so that steam may be (juite shut oil' oi' supplied in any 

 reasonable volume at any pressure by turning the head ol' tiie spindle. The 

 bottom of the spindle receives the T-tube GEB\ the joint being ground so as 

 to admit of rotation of the spindle around the tube. Air charged with nuclei 



Fig. 7. — Adjustable Nozzle for Steam Jet. Scale i. Fig. 

 Color Tube. Fig. 9.— Tubular Condenser for Ionized Gases. 



8. — Gasometer Train and Modified 



is conveyed through this tube, entering at F and coming from the identical 

 gasometer train and phosphorus tube already desci'ibed. 



To obviate the danger of steam entering the tube, EF, and (puenching the 

 ionizer, a hollow nozzle, i>, is ground into the top of the spindle and removable 

 at pleasure. This iutioduces the dust at 1 cm. above the annular opening in 

 the jet, where the pressure excess is smaller. The nozzle does not otherwise 

 interfere with the action. Should water enter the tube E, it may be removed by 

 opening the stopper G. 



The color tube as now modified is shown at (J, figure 8, the jet playing 



