First book of botany : being an introduction to the study of the anatomy and physiology of plants, suited for beginners / by John Hutton Balfour.

  • Balfour, John Hutton, 1808-1884.
Date:
1872
Catalogue details

Licence: Public Domain Mark

Credit: First book of botany : being an introduction to the study of the anatomy and physiology of plants, suited for beginners / by John Hutton Balfour. Source: Wellcome Collection.

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    grape-sugar. Cane-sugar, or sucrose (C^2H22*-^ii)' exists in the juice of some plants, such as the sugar-cane (Saccharum officinarum), sugar-maple {Acer saccharinuni), and in beet-root {Beta vulgaris). It is also found in carrots and turnii:>s, and in the young shoots of the maize or Indian corn {Zea Mais). [See Second Booh of Botany, fig. 155]. Grape-sugar, called also glucose (CgHiaOg) is a product of germination, being formed during the early growth of the embryo plant, and it exists in many kinds of fruits. It may be procured by boiling starch in dilute sulphuric acid, neutralising the acid by chalk, and evaporating the liquid till it becomes a syrui), when the sugar crystallises. Other organic substances found in the tissues of plants have nitrogen in their composition, along with carbon, oxygen, and hydrogen. The substances thus formed are usually in combination with sulphur and with alkaline or earthy phosphates. The constituents of these substances are commonly known as albumen, fibrine, and caseine. Gluten, consisting mostly of fibrine and albumen, is the glutinous part of Avlieat. It remains after the starch and the soluble constituents of the grain have been removed. Nitrogen enters largely into the composition of the tissues of animals, and there- fore is required in their food. Nitrogen is known to lis as a gas, forming 79 volumes per cent, of the atmo- sphere, and moderating the effect of oxygen on all oxidisable bodies. It entei'S into composition with hydrogen, and forms ammonia, consisting of one atom of nitrogen and three of hydrogen, HglST. Ammonia is a very pungent gas, and is slowly given off during the decay of nitrogenous animal and vegetable tissues. It is exceedingly soluble in water, and is a powerful base, uniting witli carbonic acid, and all acids, to form am- monia salts. The ammonia in the air is dissolved by rain and brought down to the soil, where it forms salts, which afford nourishment to plants. The nitrogen of tlie air does not appear to be taken up directly by plants; but, according to recent researches, it seems to bo absorbed to a certain extent by the soil, and there