Thorp’s replica of a Rowland diffraction grating

Made by Thorp, Thomas in London, England, 1905-1915.

A diffraction grating is a plate engraved with a large number of fine parallel lines. They are used in spectroscopy to analyse the spectra of stars into their compound colours. Every element has a different signature spectrum, the spectroscope allows the observer to define what elements the object is composed of. Spectroscopy was first used in astronomy in the early 1860s. One of its first uses was to determine the elements that comprise the sun. Star spectroscopes can allow a user to determine ...


Object No.


Physical Description

Optical equipment in storage box, diffraction grating, glass / leatherette / metal / fabric, designed by Henry Augustus Rowland, Baltimore, Maryland, United States of America, 1882, made by Thomas Thorp, London, England, 1905-1915, used by Sydney Observatory, New South Wales, Australia, [1905-1950]

Thorp's celluloid replica of the Rowland metal diffraction grating. The diffraction grating consists of a rectangular glass plate with a square grating etched in the centre.The grating has 14510 lines to the inch. There is a label glued above the grating and another adhered below the grating. The grating is enclosed in a leatherette case with a hinged lid.

Observatory stock number 104.


Printed text on the label above the grating reads 'The surface of the grating / must not be touched' and text below the grating reads 'THORP'S Transparency Replica of Rowland / Metal Diffraction Grating / 14510 [handwritten] lines to the inch'.



Henry Augustus Rowland developed the metal diffraction grating in Baltimore Maryland, United States of America in 1882. This diffraction grating was made by Thomas Thorp between 1905 and 1915 in London, England.


Thorp, Thomas 1905-1915


Rowland, Henry Augustus 1882



The diffraction grating was used at Sydney Observatory for demonstration purposes between 1905-1950.


Sydney Observatory 1905-1950


Credit Line

Source unknown

Acquisition Date

14 November 1983

Cite this Object


Thorp's replica of a Rowland diffraction grating 2018, Museum of Applied Arts & Sciences, accessed 17 November 2018, <>


{{cite web |url= |title=Thorp's replica of a Rowland diffraction grating |author=Museum of Applied Arts & Sciences |access-date=17 November 2018 |publisher=Museum of Applied Arts & Sciences, Australia}}


This object record is currently incomplete. Other information may exist in a non-digital form. The Museum continues to update and add new research to collection records.

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