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Description: | LMP 201 g (spurious Nat. Phil. departmental catalogue number in felt tip, removed). VICTOR MADE IN BOSTON U.S.A. TUNGSTEN MACALASTER WIGGIN CO 56470 (acid etched on the cathode limb of the glass envelope). MACALASTER WIGGIN TUBE SOLD BY BRITISH MANUFACTURERS & SOLE AGENTS NEWTON & WRIGHT LTD. 72, WIGMORE STREET, LONDON., W.( on a printed paper label originally stuck to the cathode limb of the glass envelope but removed for conservation). MINISTRY OF MUNITIONS (H.M.G.) OFFICIAL STAMP {illegible}Tube No. {illegible} Inspection No. 53130 Class No. 1. 117, PICCADILLY, W.1. ( on a printed paper label originally stuck to the cathode limb of the glass envelope but removed for conservation). 6 (stamped on the steel cathode sheath). 48810 PAT. SEP. 5.11 DEC. 30.13 JUNE 23.14 NOV 30.15 (stamped on the copper block of the cathode). MANU Macalaster Wiggin Company 1915 to 1920 Boston, The United States of America. DES after RONTGEN,Wilhelm,Conrad,von. 1895 Wurzburg, Germany. DES after CROOKES,William,Sir. 1870 London, England DES after HITTORF,Johann,Wilhelm,Professor. 1869 Munster This is a gas filled or cold cathode medical X-ray tube with a colimator or focussing ring as an extension of the anticathode. The anticathode is constructed from a block of copper with a 2mm thick inset disc of tungsten. This assembly is angled at 45 degrees to the flow of electrons from the cathode. It is rivetted into a steel tube which is clinched into the glass envelope and connected to the lead in wire by copper. The focussing ring is a press fit into the copper of the anticathode. The cathode is a dished tungsten disc supported by a steel tube clinched to a glass stem in a limb of the tube. It is welded to the platinum lead in wire by an aluminium rod.
The anode is a nickel disc on a nickel rod welded to its platinum lead in wire.
As the vacuum hardened with use a spark would pass from the anode to the side arm liberating sufficient gas to regenerate the soft vaccum. This is the Glew automatic acclusion process. All the end caps are nickel with loop connectors except the the side arm which has a screw clamp to connect to earth. The anode and anticathode are not connected by the usual coiled nickel wire which is presumably lost.
It is a Macalaster Wiggin tube. In this type of tube the electrons from the cathode were reflected from the anticathode and generated X-rays by collision with residual gas in the tube. They were operated by spark gap induction coils or later by closed core transformers. Typical ratings were 150KV. The main disadvantage was that there was no current control which meant that greater penetrating power could only be achieved by increasing the potential which decreased the wavelength. | License: | http://www.hmag.gla.ac.uk/spirit/rights/ | Publisher: | Hunterian Museum and Art Gallery, University of Glasgow | Rights holder: | Hunterian Museum and Art Gallery, University of Glasgow | Subjects: | SCIENTIFIC COLLECTION : | Source: | Hunterian Museum | Creator: | Hunterian Museum and Art Gallery, University of Glasgow | Identifier: | http://www.huntsearch.gla.ac.uk/cgi-bin/... | Language: | en-GB | Go to resource |
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