10-022. English, late 4th quarter 19th century, diamond engraved in script on the center bulb "Crookes' Radiant Matter Tube, 3 inch Spark No 2a, L. Casella London." This very rare early triple bulb Crookes' tube is made of yellow-green uranium glass, 5" long overall x 2 1/8" diameter. It is in fine overall condition and still works beautifully, the uranium glass fluorescing brightly.
