History of Science Museum: Collection Database Search

Record Details

Thermometers and Spectra Glass Plates, by H.G.J. Moseley, Manchester/Oxford, c.1913

Object is on display.
Inventory Number: 16892
Object Type:
Persons: Henry Gwyn Jeffreys Moseley
Date Created: c.1913
Place Created: Manchester England United Kingdom Europe
Accession Number: 1935-8
Brief Description: These particular pieces of apparatus were constructed and used by Henry Moseley, first at Manchester in 1913 and then at Oxford from November 1913 to the summer of 1914. He studied chemical samples using X-ray spectroscopy and hence determine their atomic number. The results were published in the ‘Philosophical Magazine’ in 1913 and 1914.

The cardboard box contains:
- 3 large spectrum plates (253 x 101mm), with spectra on half of plate
- 23 spectrum 'half' plates (252 x 50mm)
- 13 half plates coated red on one side and opaque cream on other
- 1 blank half plate
- 1 smaller plate with mostly illegible label
- 1 cased thermometer without graduations
- 1 cased barometer and thermometer
(One other spectrum half plate and coated plate on display.)

Moseley used X-rays to analyse the properties of elements in a new and brilliant way: he generated characteristic X-rays of sample elements and analysed them in the spectrometer. Moseley placed the specimens he wanted to investigate in an X-ray tube and created a vacuum by evacuating air from the X-ray tube and spectrometer. He made use of the effect that when an element is bombarded with energetic electrons X-rays with characteristic wavelengths are produced. These different wavelengths led to the X-rays being reflected at different angles from the crystal in the centre of the spectrometer. So when X-ray beams of different wavelengths hit a photographic plate they will create distinct lines. The angular position and separation of these lines are unique for each element. These values helped Harry to determine the wavelengths of the lines and hence the number of protons in the element’s nucleus.

See attached narrative 'Henry 'Harry' Moseley and his experiments' for further details.
Collection Group:
Material(s): Glass
Height Width Depth Diameter Unit
120 140 280 mm


Permalink: http://www.mhs.ox.ac.uk/object/inv/16892