Physical description

The investigation of the x-ray appears early on to have been a priority research topic at the University of Melbourne’s School of Physics. This interest was sparked by the appointment in 1889 of Professor T.R. Lyle. Lyle, who was head of the school until 1915, is thought to have been the first person in Australia to have taken an x-ray photograph. A copy of this photograph can be found in the School of Physics Archive. For this particular experiment Lyle actually made his own x-ray tube. His successor, Professor Laby, continued to work with x-rays. During the 1920s Laby worked on the x-ray spectra of atoms and in 1930 he co-published with Dr. C.E. Eddy, Quantitative Analysis by X-Ray Spectroscopy. Also with Eddy, Laby produced the landmark paper Sensitivity of Atomic Analysis by X-rays. Laby went on to have an x-ray spectrograph of his own design manufactured by Adam Hilger Ltd. (see cat. No. 38). School of Physics, the University of Melbourne Cat. No. 22. Jacqueline Eager Student Projects Placement, Cultural Collections 2005 The original X-ray tubes relied on low pressure operation. The electrons and positive ions are produced in the residual gas. Positive ions are accelerated towards the cathode and release electrons which on hitting the anode produce X-rays. These early gas X-ray tubes operated satisfactory only over a narrow pressure range.

Inscriptions & markings

Manufacturer’s mark stamped: “PATENTED/ VICTOR/ TRADEMARK/ MADE IN BOSTON U.S.A./ TUNGSTEN” A white circular stamp, stamped near the manufacturer’s mark: “[illegible]TER WIGGH[illegible]” Stamped label: “NAT. PHIL. LAB./ No./ UNIV. OF MELB.” Inscription on the end face of the copper piece: “PAT. SEP 5’ 11 DEC. 30’13/ JUNE 23, 14 NOV. 30.15/ 43835”