Humboldt State University ® Department of Chemistry
Robert A. Paselk Scientific Instrument Museum
Kipp's Gas Generating Apparatus
Kimble Glass Company
Humboldt College; c.1958
Used for the automatic, on-demand generation of small quantities of laboratory gases such as carbon dioxide and hydrogen sulfide. This particular piece of apparatus was used at Humboldt State College to generate hydrogen sulfide (H2S) for use in qualitative analysis to precipitate various metal ions as their sulfides. In use the central bulb was charged with iron sulfide (FeS) chunks to the top of the central cylinder. Hydrochloric acid would then be introduced, with the side stopcock open, into the upper bulb and flow down to the lower bulb until its level reached and covered the iron sulfide. The acid and iron sulfide would now react to generate hydrogen sulfide gas, which could be drawn off through the stopcock and bubbled into test tubes etc. When no more gas was needed the stopcock would be closed and the gas generated would force the acid down into the lower bulb and then into the upper bulb, until it no longer contacted the iron sulfide, bring the reaction to a halt. Opening the stopcock to tap more gas then allowed the acid level to rise, generating more gas etc.
Kipp's apparatus was invented by Petrus Jacobus Kipp (1808-1864), a pharmacist in Delft, the Netherlands. He set up a business in scientific apparatus and chemicals in 1830. Kipp published a description of his apparatus in a Dutch journal in 1844. The oldest known copy of a Kipp generator, thought to date between 1845 and 1875, is at the Museum Boerhaave in Leiden. It is 62 cm high.1
Some early descriptions of Kipp's apparatus and its use are provided below:
The apparatus is 63 cm high to the top-lip of the upper bulb, 86 cm to the top of the thistle-tube. The base is 27 cm in diameter. The upper and lower bulbs connect through a 71/60 standard taper joint (etched in middle bulb). EXAX / USA is etched into the center of the upper bulb in small (4 / 2 mm) letters. This apparatus has a nominal capacity of 2,000 mL. The glass has a light yellow-green tinge to it, and tool marks are quite obvious on the apparatus, especially on heavy lips of the two stoppered orifices. The Stopcock is Kimax with a #4 standard taper plug. The thistle tube is etched KIMAX USA on the funnel-bulb.
This apparatus by Kimble (Exax) is illustrated and described as item 32420 on pg. 496 of Catalog No 63, Laboratory Instruments Apparatus and Supplies. Braun-Knecht-Heiman-Co. (Division of Van Waters & Rogers, Inc.) San Francisco. (1961). The large, 2,000 mL version, which we have, listed for $85.30. This apparatus replaced a smaller version of which only the lower reservoir/bulb currently exists (1998).
1 Personnal communication: Peter de Clercq, Museum Boerhaave, Leiden, The Netherlands. Mr. de Clercq noted two papers on Kipp: first [in Dutch] A. Tutein Nolthenius, De Natuur. (1943) pp. 29-43; second [in French] H. Snelders, "Le pharmacien P. J. Kipp (1808-1864) et son appareil," Revue d'Histoire de la Pharmacie, vol. XXI (1972) pp. 3-12. This later paper has reproductions of early plates of consecutive versions of Kipp's apparatus from the 1840's.