Phenomena of life maintained and controlled by two antagonistic principles of innervation. Anatomy of the iris reviewed; value of the irian variations in diagnosis. Diphtheria. Poisoning treated on physiological principles.

  • Freel, J. G.
Date:
1864
Catalogue details

Licence: Public Domain Mark

Credit: Phenomena of life maintained and controlled by two antagonistic principles of innervation. Anatomy of the iris reviewed; value of the irian variations in diagnosis. Diphtheria. Poisoning treated on physiological principles. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    The phenomena of life are maintained by two co-ordinate antagonistic systems of innervation, controlled by the cerebro- spinal, and the sympathetic centres. Nerve-fibres for the con- duction of innervation to the capillaries, pass with motor fibres through the sympathetic ganglia, and possess the power of contracting the capillaries, and with sensitive fibres through the sensory ganglia, and are endowed with the special function of dilating the capillaries. Normally, these opposing nervous forces maintain an equil- ibrium commensurate with the due performance of organic function, but any disturbing influence capable of producing a preponderance of either would, when transcending the boundary of health, induce disease. Physiological action.—Experiments on the stomach of St. Martin prove, that immediately on the introduction of food the mucous membrane becomes turgid and reddened with the influx of blood, and that the gastric fluid begins at once to be secreted i but instantly on the removal of the ingesta, the membrane becomes again pale, and the secretion of the gastric fluid ceases. Here it is evident that the instantaneous sanguineous turgescence and its equally quick disappearance must be under the control of sentient principles. The sensation produced on the sentient nerves of the mucous membrane, by the contact of the food, is communicated to their cerebro-spinal centres and an order thence transmitted along the dilating nerve-fibres, for the capillaries to expand, that the elements from which the solvent of the food is elaborated may be sufficiently supplied. But the negative sensation caused by the removal of the ingesta is conveyed by the ganglionic sensory nerve-fibres to their respective centres, and a mandate returned through the contracting nerve-fibres, for the capillaries to shut off the blood, and thus prevent an unnecessary expenditure of vital fluid. There is no doubt from the harmonious action but when one force is in requisition that the other, being notified through an intercommunicating branch, abates its innervation.