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Pig. 38. Minor apparatus in Durig's laboratory» Vienna.
The Kjeldahl digestion apparatus may be seen in the background.
The general use of the Teclu burner is here to be noted. The large
glass apparatus supported on a ring stand is an automatic pipette for
measuring sulphuric acid for Kjeldahl work. Prof. Durig's sodium
hydroxide apparatus for delivering caustic soda is in the background.
Two foms of the mercury vacuum switch are shown in the foreground and
the cork boring machine at the extreme left. Note the general use
of iron gauze interwoven with asbestos.