Science 2(27): 178 (August 10, 1883)
Influence of diminished atmospheric pressure on the growth of plants.

Experiments conducted by Wieler at Tübingen show, that, all other external conditions being the same, plants will grow more rapidly under diminished atmospheric pressure. Thus, if a specimen of the common Windsor bean (Vicia faba) be grown in a receptacle in which the pressure of the air can be controlled, it will be found to grow faster until the pressure has been diminished to 100-300 mm.; the normal pressure under which the ancestors of the plant have flourished being, of course, not far from 760 mm. If, however, the pressure is reduced below the smaller figure given above, the rate of growth diminishes. Wieler found that the curve of growth of the sunflower is about the same as that of the bean. It was further shown by his experiments, that growth is retarded by increased puressure until the minimum is reached at 2-2 1/2 atmospheres, from which point there is again an increase. Although the short abstract of these interesting results so far published is meagre in the extreme, it indicates that the field entered upon by Wieler (and by Bert in France) may compel us to revise some notions now held in regard to the adaptation of plants to their surroundings in past ages, and at the present time upon high mountains.—(Botan. zeit., July 6.) G.L.G.

Atmospheric Pressure, Plant Growth & Development