Accession No
3774
Brief Description
rolling parallel rule by W. H. Harling Ltd., English, early 20th Century
Origin
England; London; 117 Moorgate
Maker
W. H. Harling Ltd.
Class
drawing
Earliest Date
1900
Latest Date
1925
Inscription Date
Material
wood (boxwood, mahogany); metal (brass)
Dimensions
box length 405mm; breadth 94mm; thickness 40mm
Special Collection
Provenance
Donated, 1990.
Inscription
‘W. H. HARLING LTD. 117. MOORGATE LONDON
I.R.W. STILEMAN.
INCHES & 10THS’
Description Notes
Boxwood rule with brass bar and rollers. Protractor along one edge. Fitted mahogany box, one hinge missing. Small screwdriver in case (probably not part of original instrument).
Condition good; incomplete (2 sliding hooks to secure a missing object in lid of box)
References
Events
Description
Parallel rule
Used by architects, engineers, cartographers and on nautical charts, the parallel rule is used for drawing parallel lines accurately. It is also used in conjunction with a scale rule for producing orthogonal drawings (with lines in non-parallel direction as well). The pivoting links can be extended to the required distance, but this makes the instrument liable to error for larger drawings because the extension is changed by hand, and can be varied accidentally.
18/10/2002
Created by: Saffron Clackson on 18/10/2002
FM:44450
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