English: Widmer column/air condenser, chemical laboratory scale simplified modern representation.

This representation of a research laboratory-scale Widmer column—a complex type of air condenser combining Golodetz-type concentric tubes and a Dufton-type glass rod-and-wound-spiral—was created for pedagogical purposes, based on references 1 and 2 (Widmer 1923 dissertation and publication, supported by various secondary sources such as Krell's 1982 Handbook of Laboratory Distillation, and Armarego's Purification of Lab Chemicals). See the latter for "pro's" and the former for "con's", on the Widmer column.

Changes: Stoppered seal of the original outer dead air space design was modernized to a ring seal, the J-shaped discharge tube was omitted for simplicity of description, and top and bottom ports were converted to appear as tapered ground joints (here, matching a side-by-side appearing Vigreux column from the important earlier image effort of User:YassineMrabet on the Vigreux). Finally, limited numbering and colored arrows were added to streamline legend descriptions in articles. If photographs of Widmer columns ever make their way into Wikimedia Commons, this schematic image should considered complimentary, for ease of explanation. Note, had the Swiss not a 70 year author post partim copyright restriction on reproducing such content, I would have simply uploaded the historically more interesting, and approximately as easily understood original Widmer images. Alas.

[File created from available individual chemistry graphic arts components, by simple editing in GraphicConverter9.] Le Prof

References: 1. Gustav Widmer, 1923, "Über die fraktionierte Destillation kleiner Substanzmengen" [doctoral dissertation], der Eidgenössischen Technischen Hochschule (ETH), Zürich, der Schweiz, approved 1923, DOI 10.3929/ethz-a-000090805, see also [1], accessed 14 February 2015. 2. Gustav Widmer, 1924, "Über die fraktionierte Destillation kleiner Substanzmengen," Helvetica Chimica Acta, 7(1), pp. 59–61, DOI 10.1002/hlca.19240070107, see also [2], accessed 14 February 2015. [Note, the 1927 reference to a related Widmer distillation article in Helv. Chim. Acta appears to be an error on the part of L.P. Kyrides, (see Org. Synth, 1940, 20, pp. 51 ff).]