Tracerlab Glass Wall GM (ca. 1950s)
This glass walled GM tube was manufactured by Tracerlab Inc., of Boston, Massachusetts. Unfortunately the model number on the label is barely discernible. It appears to be 31 something or other. In other words, a mystery tube!
There is a slight indent approximately two inches down from the top of the tube. Below this point the glass wall seems to get thinner. My best guess is that this is a "dipping" counter for quantifying low energy beta emitters in liquids.
Size: 7 1/4” long and 7/8” diameter
Cathode: Metallic coating on inside of glass wall
Base: Four prong ceramic base
Donated by Ron Kathren.