Object data
wood and brass
length 109 cm × length 191 cm (max.) × width 9.3 cm
Petrus van der Loo
The Hague, The Hague, c. 1850
wood and brass
length 109 cm × length 191 cm (max.) × width 9.3 cm
...; transferred from the Ministerie van Marine (Department of the Navy), The Hague, to the museum, 1883
Object number: NG-MC-81
Copyright: Public domain
Patent model of a ladder consisting of two parts. The extending part has a small wheel at the top of each leg and is moved with a fixed spindle and crank at the bottom of the standing part; the rope runs through a sheave on one of the rungs back to the bottom of the extending part. Two ratchets prevent the extending part from sliding back. The extending part is also fitted with a support that automatically unfolds when the ladder is set against a wall. Some parts of the support seem to be missing.
Petrus van der Loo (1806-1864) obtained a five-year patent for his improvements to ladders1 in 1850. His model was shown at the Exposition Universelle of 1855 in Paris.2
Expositions des produits de l’industrie de toutes les nations, 1855. Catalogue officiel, Paris [1855], p. 381; J.M. Obreen, Catalogus der verzameling modellen van het Departement van Marine, The Hague 1858, nos. 76-81; G. Doorman, Het Nederlandsch octrooiwezen en de techniek der 19de eeuw, The Hague 1947, no. 1845, p. 305; A.A. Lemmers, Techniek op schaal. Modellen en het technologiebeleid van de Marine 1725-1885, Amsterdam 1996, pp. 260, 355
J. van der Vliet, 2016, 'Petrus van der Loo, Model of a Ladder, The Hague, c. 1850', in J. van der Vliet and A. Lemmers (eds.), Navy Models in the Rijksmuseum, online coll. cat. Amsterdam: hdl.handle.net/10934/RM0001.COLLECT.242806
(accessed 13 November 2024 03:13:19).