Tissot spirometer used for BMR measurements. From Can Med Assoc J. 1918 June; 8(6): 491–509. The determination of basal metabolism by the “Respiratory-valve and spirometer method” of indirect calorimetry, with an observation on a case of polycythemia with splenomegaly.Maude E. Abbott
From: Basal Metabolism: Its determination and Application. FB Sanborn. Page 123. Published 1922. Variation of a Krogh Spirometer. Described in text as being 17 inches high and weighing 40 pounds.