A New Form of Apparatus for Determination of Gases by Manometric Measurement.

Abstract

In the course of a certain study on hemoglobin it was necessary to mix thoroughly the solution to be analysed with the reagent before evacuation and extraction. As this could not be done in Van Slyke's apparatus, 1 we have devised a new form of the gas burette which, besides serving our special purpose, possesses certain advantages over the form now generally used.

The principal feature of the apparatus (Fig. 1) is that 2 chambers are used instead of one. The extraction is carried out in one chamber (A) while the gas is measured in another (B).

The new apparatus is used essentially in the same way as Van Slyke's. The apparatus is first rinsed with H₂O, and both chambers, including the cock spaces, are completely filled with mercury. The solutions are then introduced into chamber A and the extraction is carried out as usual. On account of the high density of mercury it is desirable to evacuate chamber B also before shaking the apparatus. When the extraction is finished the upper cock is turned to connect A and B. If the pressure in A is high, the mercury in cock space b and above it is pushed over into B. If this does not happen when the cock is opened, shake the apparatus for a few seconds. Mercury is admitted into A and the solution is brought just to the top of A or to a mark slightly above the cock space b—according to how the chamber B has been graduated. The lower cock is then turned to connect B to the manometer and the reading of the pressure is taken in the usual manner at 2, 1 or 0.5 cc.