Accession No
6494
Brief Description
catalogue of the Mensing collection, R. S. Whipple’s copy, by Frederik Muller and Company, Dutch, 1924
Origin
Netherlands; Amsterdam
Maker
Frederik Muller and Company
Class
books; ephemera
Earliest Date
1924
Latest Date
1924
Inscription Date
1924
Material
paper
Dimensions
length 285mm; width 190mm; depth 50mm
Special Collection
Provenance
Purchased from an individual at a Scientific Instruments Fair on or before 10/05/2011. This copy of the catalogue was likely in the Whipple Collection previously; there is a Whipple bookplate inside.
Inscription
"R. S. Whipple" [signature on cover]
"Heilbronner bought most of the collection in the Palace of Strozzi, Florence, about 1900 (took 40 years to collect)" [note on title page in Whipple's hand]
Description Notes
Black and white printed catalogue of Mensing Collection, with several handwritten notes by R. S. Whipple. Signed by Whipple on top right of front cover. Bears Whipple collection bookplate on inside cover.
Catalogue comprises an introduction by the cataloguer, Max Engelmann, brief descriptions of objects in collection (divided by type into seven separate sections (see below)), a list of references and an index (all in German).
The seven sections of scientific instruments are listed in the contents page as:
I. Armillarspären
II. Himels- und Erdoglben
III. Astrolabien - Astrologische Scheiben
IV. Mathematisches Kleingerät - Zeichenhilfsmittel - Maßstäbe
V. Mathematische Instrumente für astronomische, geodätische und artilleristische Meßvahren - Wegmesser
VI. Sonnen-, Nacht-, Sand- und Räderuhren, Kalenderäte
VII. Physikalische und chemische Instrumente
Also a page of notepaper with notes in Whipple’s hand (in pen and pencil). On one side is a series of observations on the collection, dated “Oct 29 : 25” and entitled “Notes re Mensing Collection” . On the reverse are a series of rough tallies concerning costs of travel, and a brief schedule.
Complete
References
Events
Description
This catalogue of the dealer and collector Anton Mensing's personal collection of scientific instruments was produced by the auction house Frederick Muller & Co. for a 1924 sale. This was Robert Whipple's own copy with his notes. In the 1950s, Whipple Museum curator Derek Price identified two 1920s forgeries in the Museum's collection that were copies of original objects in this sale: Wh.0306, a gilt brass nocturnal, and Wh.0305, an astrolabe purportedly by Johannes Bos.
By comparing museum catalogues and then tracing the provenance of matching instruments, Price was eventually able to identify twenty-seven fakes across twelve collections in Europe, all of which could be connected back to two sales run by Mensing in 1911 and 1924. The forger appears to have had access to the original instruments when copying pieces from this 1924 sale.
Price did not think that Anton Mensing was responsible for the production of these forgeries. Rather, he noted that at least a dozen of the ‘Mensing fakes’ had passed through the hands of an Amsterdam dealer that he named only as “Mr. X”. Subsequent scholarship has identified this man as Christiaan Feeterse. Tellingly, Christiaan’s brother Jacob was a fine silversmith and artefact restorer who’d been employed by Anton Mensing. It seems likely that Jacob had secretly copied objects from both Mensing’s collection and the 1911 sales catalogue; his brother then sold these copies as genuine pieces.
07/10/2026
Created by: Hannah Price on 07/10/2026
FM:47003
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