porometern.

1911 F. Darwin & D. F. M. Pertz in Proc. Royal Soc. B. 84 137 We believe that a much more intimate knowledge of the living stoma and its movements would be necessary to prove his contention..that ‘the regulatory function is almost nil’. With a view to testing the question we have designed an instrument which we propose to call a porometer. The idea is to estimate changes in the stomata by recording the change in the velocity of a current of air drawn through them in the living leaf.

1939 Geogr. Jrnl. 94 124 The effect of the continuous illumination of the arctic summer in the stomatal mechanism of leaves was studied by porometers.

1970 Nature 25 July 377/2 The stomatal activity of fully hydrated..broad bean plants..was investigated using a recording porometer attached to the second mature leaves from the apex.

1975 G. Anderson Coring iv. 77 The basic instruments [for core analysis] are the porometer for porosity measurements, the permeameter for permeability measurements, and the saturation retorts for saturation measurements.

1998 Materials World Apr. 256/3 The Porometer provides information on all aspects of through-pores, including bubble point (largest pore), mean pore size, pore size distribution, permeability, pressure hold, and integrity.

1911 Proc. Royal Soc. B. 84 139 The porometric method is a direct one.

1964 Jrnl. Ecol. 52 153 The use of a porometric technique allows estimations of water loss and stomatal aperture to be made on the same sample.

1996 Jrnl. Exper. Bot. 47 925/2 Porometric measurements revealed that stomatal conductance of plants grown under elevated CO₂ was lower than that of control leaves.