Les instruments du calcul savant > Instruments d'intégration conservés au musée des arts et métiers


Integraph with transfer of direction by cog-wheels, system Abdank-Abakanowicz/Napoli
Maker: P. Barbier & Cie., Paris; instrument no.: none; c1886 (see Abdank-Abakanowicz 1886, 39)
Inventory: CNAM, inventory no.
44165-0001- (box: inv.-no. 44165-0002-)
Details: Signed: »Intégraphe / S
me ABDANK ABAKANOWICZ / ET / NAPOLI / - / P. BARBIER & Cie Constructeurs / PARIS«; entry CNAM: 2001
References: Abdank-Abakanowicz 1886, ix and Abdank-Abakanowicz 1889, 42-44 (especially fig. 45)

Until 1886 all the integraphs designed by Bruno Abdank-Abakanowicz remained prototypes or one-of-a-kind instruments. Due to the one or the other weakness in design and/or execution, commercial production was out of sight. By 1886, however, the cogwheel mechanism for direction transfer - probably contributed by David Napoli - had resulted in a reliable prototype (see CNAM 13300-0001-) and obviously made a commercial production of instruments promising. These were made by the Barbier workshop (P. Barbier et Cie, 5 place du Panthéon, Paris; see Abdank-Abakanowicz 1886, ix, footnote 1), who had already furnished the prototype. The enlarged and revised German edition of Abdank-Abakanowicz 1886, i.e. Abdank-Abakanowicz 1889, showed how this serial instrument looked like:

Integraph system Abdank-Abakanowicz/Napoli, commercial version by Barbier
Fig. 43+44 = Abdank-Abakanowicz 1889, 43; fig. 45 = Abdank-Abakanowicz 1889, 44

Until a few years ago, only these illustrations and the description in the book mentioned a commercial production, but no real instrument was known. This changed in 2001, when an integraph was offered to the CNAM, which is easily identified as being one of the commercially produced Barbier integraphs.

Integraph system Abdank-Abakanowicz/Napoli, commercial version by Barbier

Integraph system Abdank-Abakanowicz/Napoli, commercial version by Barbier, details

Integraph system Abdank-Abakanowicz/Napoli, commercial version by Barbier, signature

But production of this special Barbier version will not have lasted long, as Abdank-Abakanowicz and Napoli were interested in the further development of the integraph even after the successful completion of the Barbier model. Probably only a short time later the cooperation with Coradi in Zurich must have started, which finally resulted in the 1888/89 version of the Coradi integraph, system Abdank-Abakanowicz. This instrument completely overshadowed the Barbier integraph, of which nothing was heard ever after.



The Barbier serial instrument, now in the collections of the CNAM, has of course a history of its own which can be traced back to the end of the 1930s. The Astrophysical Institute (Institut d'Astrophysique, IAP) was created in these days; Henri Mineur, its first director, was able to buy the integraph with the help of funding by the CNRS (Centre National de la Recherche Scientifique). Regrettably, it is not known where the instrument came from. The first Ph. D thesis (dissertation) of the Institute was written by Jean-Claude Pecker, today Membre de l'Institut (member of the French Academy of Sciences) and professor at the College de France. He used the integraph to study the transfer of radiation in a star's atmosphere. In order to facilitate the use of the instrument, he replaced the original tracer pin by a tracer lens of his own construction. When Mineur's office was dissolved, Pecker took care of the integraph in order to avoid it being scrapped. In May 2000 and with the consent of the then director of the IAP, Pecker offered the integraph to the CNAM. In 2001 it was added to the CNAM collection.