Sundial making tool


Buy this image as a print 

License this image for commercial use at Science and Society Picture Library

Brass semi-circular horary quadrant, 17th century (6-inch radius)
Science Museum Group
© The Board of Trustees of the Science Museum

Horizontal instrument or sundial making tool, unknown maker, London, 1620-1635.

On the reverse is a stereographic projection for c. 52°, folded into a semicircle with arcs for sun’s declination and hour angle (to quarter hours) These arcs continue above the Cancer circle through the zenith (unusual). Path of ecliptic marked with months/days. Scale on edge gives declination and signs of zodiac. Rule delineated to give the sun’s altitude.

On the obverse is a protractor scale around circumference in the standard Elias Allen style. Inside, a number of arcs giving the angles of the hour lines on a horizontal sundial (to quarter hours) for a range of English latitudes with 1° steps. These are probably in a second, contemporary, hand.

While the maker is unknown, this instrument is likely to have been made in the workshop of Elias Allen.

This instrument is used for time telling and all the associated features (sunrise, sunset, day length, declination, sun’s altitude and azimuth as described in William Oughtred’s ‘The Horizontal Dial’.

It is also a very rare design template for the production of standard horizontal sundials for latitudes across England.


Object Number:
sundial making tool
  • furnishing and equipment
  • measuring device - instrument
  • timepiece
Mrs. Philiss D. Lee

Cite this page


We encourage the use and reuse of our collection data.

Data in the title, made, maker and details fields are released under Creative Commons Zero

Descriptions and all other text content are licensed under a Creative Commons Attribution 4.0 licence

Using our data


Download catalogue entry as json

Download manifest IIIF

Our records are constantly being enhanced and improved, but please note that we cannot guarantee the accuracy of any information shown on this website.