Glew's Scintilloscope (ca. 1904-1921)
Glew's Scintilloscope was introduced in 1904, the year following Crookes' invention of the spinthariscope. It was produced at least until 1921. The difference between the two is that the radioactive and luminescent materials were not incorporated into the body of the scintilloscope.
When purchased, the scintilloscope usually came with a pitchblende screen, and in some cases a radium and thorium screen. Each screen consisted of a radioactive source in direct contact with luminescent material (probably ZnS).
The scintilloscope to the right is a little unusual—to be used, the eyepiece had to be removed from the bottom section (see below right). Unlike the more common version of the scintilloscope (shown towards bottom of the page), this example didn't come with a radioactive screen or a leatherette case. Perhaps they were sold separately.
The paper label on the bottom of the box is shown to the right.
Notice that the scintilloscope in theabove advertisement is threaded so that the focus could be adjusted by turning eyepiece. Neither example shown here has such a feature.
For what it is worth, F. Harrison Glew was a pharmacist at the British Medical Research Council's radium laboratory.