An experimental inquiry into the physiological action of ergot of rye / [Samuel Wright].

  • Wright, Samuel
Date:
[1840?]
Catalogue details

Licence: Public Domain Mark

Credit: An experimental inquiry into the physiological action of ergot of rye / [Samuel Wright]. Source: Wellcome Collection.

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    grains of rye in every stage of decay, but was not able to discover in either the eggs or larvae of any insect. I therefore conclude, that the puncture of the fly is for the purpose of extracting its food from the rye, and not for the deposition of its eggs.* * * § Wiggers adopts the theory of Decandolle respecting the forma¬ tion of ergot, for he discovered that the white dust which is sprink¬ led over the surface of the spurs, will, if applied to the roots of a sound plant, generate the disease.”!* On the contrary, Hertwig, a German physician, has concluded from a series of careful experiments, that the disease is incommu¬ nicable by contact. He surrounded the ear when in flower, with the powder of spurred rye, without in any degree affecting the healthiness of the plant or its grain.J My own experiments correspond in their results with those of Hertwig. I have sown rye in conjunction with ergot, both in powder and in substance, without the process of germination be¬ ing either retarded or modified, or anything but a natural and healthy maturation resulting. I have regularly watered rye, from the sowing of the seed to its period of ripening, with a solution of ergot, but without producing a trace of the disease. Nor does the direct application of the powder of ergot to the ears of rye seem in any way to affect them. Indeed, a solution of ergot does not appear to have any influence upon vegetables. I have watered turnips, stocks, slips of currant trees, &c. for weeks together, with¬ out injuring them in the least. Should the experiments of Wiggers be correct, they will mate¬ rially tend to establish the theory which he suggests ; but on com¬ paring the small quantity of fungin, a harmless substance, with the prevalence of oil in the ergot, the presence of which requires a dif¬ ferent explanation, I cannot help concluding that the hypotheses which ascribe the formation of this excrescence to atmospheric warmth and moisture, are the most accordant with circumstances, and the least liable to objection. Tessier has also rendered this idea more probable, by showing from careful and elaborate inves¬ tigation, that the district of Sologne, which is more exuberant in the production of ergot than any other place, is thus peculiarly adapted to its production. And it is well known that nothing so soon produces ergot as a storm of rain falling upon rye situate in a hot latitude, and in a moist rich soil.§ Further, the grains are sometimes found to be only partially ergotted, one-lialf being * Annals of Philosophy, N. S. Yol. xi. p. 14. f Inquisitio in Secale Cornutum, &c. Commentatio prasmio regio ornata. Got- tingffi, 1831. X Lorinser, Beob. und Vers, iiber die Wirkung des Mutterkorns, 1824. Quoted in Robert’s paper, 28. § Duncan’s Med. Com. Vol. ix. p. 78.
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