Crookes tubes are now used only for demonstrating cathode rays.

He was a pioneer of vacuum tubes, inventing the Crookes tube.

The electronic vacuum tubes invented later around 1906 superseded the Crookes tube.

His early experiments were with Crookes tubes, a cold cathode electrical discharge tube.

The Crookes tube was improved by William Coolidge in 1913.

A Crookes tube is a sealed glass container in which two electrodes are separated by a vacuum.

Later experimenters painted the back wall of Crookes tubes with fluorescent paint, to make the beams more visible.

Thomson constructed a Crookes tube with a near-perfect vacuum.

He developed the Crookes tubes, investigating cathode rays.

These were called Crookes tubes.

Crookes tubes were used in dozens of historic experiments to try to find out what cathode rays were.

An illustration of a "maltese cross" Crookes tube.

The nature of the Crookes tube "cathode ray" matter was identified by Thomson in 1897.

It was a cold-cathode diode, a modification of the Crookes tube with a phosphor-coated screen.

Wilhelm Röntgen discovered X-rays using the Crookes tube in 1895.

The many uses for X-rays were immediately apparent, the first practical application for Crookes tubes.

Crookes tubes were unreliable and temperamental.

Many ingenious types of Crookes tubes were built to determine the properties of cathode rays (see below).

Philipp Lenard wanted to see if cathode rays could pass out of the Crookes tube into the air.

The 19th century saw increasing research with evacuated tubes, such as the Geissler and Crookes tubes.

The first true electronic vacuum tubes, invented around 1906, used this hot cathode technique, and they superseded Crookes tubes.

Thomson constructed a Crookes tube with an electrometer set to one side, out of the direct path of the cathode rays.

In 1896, Wright had been experimenting with Crookes tube of spherical shape to generate long exposure x-ray photographs.

William Crookes invents the Crookes tube which produces cathode rays.

In 1895, Wilhelm Röntgen discovered X-rays emanating from Crookes tubes.