On flax, and the practicability of extending its cultivation in Ireland : together with directions for the proper management of that crop / by Edmund W. Davy.

  • Davy, Edmund William, 1826-
Date:
1865
Catalogue details

Licence: Public Domain Mark

Credit: On flax, and the practicability of extending its cultivation in Ireland : together with directions for the proper management of that crop / by Edmund W. Davy. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    matter, the phosphoric acid, or the potash removed from the soil; so that we cannot regard Flax as a particularly exhausting crop, as is ge- nerally done. But here we view it under the most unfavourable aspect; for it rarely happens that the whole of the crop is sold off the farm, but the seeds, or a portion of them, are used for feeding purposes, and the straw is very commonly steeped there, and it is only the Flax fibre that is disposed of. If, however, the water which is used in steeping the Flax was em- ployed for irrigation, and the expressed seeds or linseed cake, for feed- ing the cattle on the farm, we would return to the soil almost all the mineral matters taken up by the plant; for the Flax fibre and oil—the two most important products of this plant—retain, after proper prepa- ration, but a very small proportion of mineral matters—those of the straw remaining to a great extent in the water used for steeping, and those of the seed in the expressed cake. These statements are borne out by the analyses of Sir Robert Fane, the late Professor Johnston, Messrs. Way and Ogston, Dr. Hodges, and other chemists, who have investigated this subject, and have all main- tained the non-exhausting characters of Flax if properly cultivated. From the elaborate and important investigations of Messrs. Way and Ogston on the mineral constituents of plants, these gentlemen have been led to conclude that an average crop of Flax contains a larger amount of mineral matter than an average crop of any of our cereals pro- duced from the same extent of ground ; but that only a small portion of that matter belongs to the fibre, the part of the plant which is permanently removed from the soil, and that this consists almost entirely of compara- tively valueless substances. The really valuable soil constituents, they find, are contained chiefly in the leaves, which in a great part drop off on the field, in the seed and seed vessels (which should be returned to the soil in the form of manure); and, lastly, in the organs of the stalks, irrespective of the fibre. They have further ascertained, that about four-fifths of the soil constituents contained in the stalk, and those the most valuable (phos- phoric acid, potash, &c.), are extracted by the water during the operation of steeping; and that nearly three-fourths of the remaining portion are again separated with the woody parts by the scutching, &c., leaving only a minute quantity (comparatively speaking) of mineral matter in the fibre. Consequently, the results of those gentlemen confirm, in a most satisfactory manner, the statements of other chemists as to the Flax plant, the cultivation of which by no means produces a necessary exhaustion of the soil, which almost ceases when the refuse matters obtained in the separation of the fibre, especially the water used in steeping the Flax, are returned to the soil. From Dr. Hodges’ experiments, he calculates, that if the fibre were only sold off the farm, a crop of two tons of straw per acre would re- move only about five pounds of mineral matter—a quantity too small to exercise any appreciable injurious effect on the fertility of the soil.
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