Elements of agriculture and vegetation. To which is added, an appendix, for the use of practical farmers / [George Fordyce].

  • George Fordyce
Date:
1796
Catalogue details

Licence: Public Domain Mark

Credit: Elements of agriculture and vegetation. To which is added, an appendix, for the use of practical farmers / [George Fordyce]. Source: Wellcome Collection.

    87/122 (page 83)
    [ «3 ] I LIGHT is alio necefiary for the Growth of a Plant, but not fo much fo as Air. Moft Leaves have two Surfaces, one of which is always expofed to the Light; and if the other is turned to it (by altering the Pofition of a Branch) the Growth is frequently flopped, until the Leaves turn themfelves to it again. This fmooth Side of the Leaf therefore, being that which is a<5ted upon by the Air and Light, would appear to be that Part by which a Plant principally lives ; and in many Plants the Leaves fhut themfelves up, fo as to cover this fmooth Side on Expofure to cold Air, noxious Vapour, f • % 4 » • Darknefs, or even upon being touched. The Want of a fufficient Quantity of Light, prevents the Plant from forming its proper Juices (except Mucilage and Sugar) deprives it of its Blue Colour (the Green confiding of Blue and Yellow) leaving it either Yellow or Colour-lefs, makes it run up weak, and prevents the Im- pregnation of the Seeds. Want of a fufficient Quantity of Air and Light, more efpecially prevent the Impregnation of the Seeds. MEAT in a moderate degree, according to die Difpofition of the Plant, makes the Leaves flourifh, and the Stem ftrong, provided the Soil is fufficiently moift -> in a very great Degree it F 2 makes