The Machlett x-ray tube was produced to ‘provide electrostatic protection for the filament (cathode) so as to permit long life to be achieved at operating voltages in the range 100-300kV’i .
The x-ray tube was designed and manufactured by E. Machlett & Son who were specialists in scientific glass instruments. The American company, who were established in New York 1897, began as a single shop and soon grew into an internationally recognised firm. The Machlett x-ray tube was patented in April 1934, with the object at the School of Physics being dated to 1937. It is possible that the x- ray tubes were used by Professor T.H Laby’s x-ray groupii.
The development 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 a x-ray photograph iii. A photocopy 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, Laby, continued to work with x-rays. During the 1920’s he worked on the x-ray spectra of atoms and in 1930 he, along with Dr C.E. Eddy, published Quantitative Analysis by X-Ray Spectroscopyiv . Also with Eddy Laby produced the landmark paper Sensitivity of Atomic Analysis by X-rays. Laby went on to have a x-ray spectrograph of his own design manufactured by Adam Hilger Ltd.
Student Projects Placement, Cultural Collections 2005
iMachlett X Ray Tube, Physics Museum Archive, University of Melbourne, p.1
ii \'The School of Physics\' in the University of Melbourne\'s Official Opening of the New Physics Building, February 1974, p.7.
History of object: This X-ray tube was designed to provide electrostatic protection for the filament (cathode) so as to permit long life to be achieved at operating voltages in the range 100-300kV. It is not certain whether the tube was in use within the School by Professor Laby’s X-ray group or whether it was presented to the School by a medical user. It would be somewhat surprising if it fitted into this School of Physics Research Program at a date as late as 1933 when tubes with demountable anodes were in use.