Untersuchungen über die Respiration und den Gesammtstoffwechsel des Menschen^1,2

The California apparatus for respiration trials with large animals

“…For these reasons, the open-air-current system, known as the Pettenkofer type, has been found more suitable for the California Experiment Station. The original disadvantage of this apparatus-that one could determine only the CO 2 production but not the O 2 consumption of the animal-has been overcome by Sonden and Tigerstedt (1895), who substituted for the steady absorption of the CO 2 of an aliquot air ,current, the collection of a composite sample that could later be analyzed for both CO 2 and O 2 in the Petterson-Sonden gas analysis apparatus (Petterson, 1886). The old Pettenkofer method was therefore combined with that of Tigerstedt for obtaining checks on the results; and this respiration apparatus would be classified as a combined Tigerstedt and Pettenkofer open-air-current enclosure apparatus.…”