Chemistry of the albumens : ten lectures delivered in the Michaelmas term, 1904, in the Physiological Department of University College, London / by S.B. Shryver.

  • Samuel Barnett Schryver
Date:
1906
Catalogue details

Licence: Public Domain Mark

Credit: Chemistry of the albumens : ten lectures delivered in the Michaelmas term, 1904, in the Physiological Department of University College, London / by S.B. Shryver. Source: Wellcome Collection.

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    situ, without considerable damage to its more delicate parts ; it is impossible to remove an albumen from its position in the living body without subjecting it to a certain amount of damage. Still, in spite of this, we can, by our somewhat crude labora¬ tory methods, gain a certain amount of insight into its general construction, and ascertain to a very great extent the parts of which it is composed, although we are at the present day still far from being able to reconstruct the machine from those parts, and so synthesise an albumen. We will now proceed to investigate the general properties of an albumen. As an example, we might take the white of egg as a product which is an easily accessible type of an albumen ; this substance, “ Eiweiss,” is, in fact, the generic name in German for the whole class of albumens. A filtered solution of egg albumen in water has certain properties which can be readily demonstrated. On heating, the albumen is rendered insoluble—coagulation takes place. This illustrates the readiness with which a change takes place in a “ natural albumen,” as we shall term the body existing in a normal functioning state in a living organism. Furthermore, the organic matter in the solution is incapable of passing through vegetable parchment. We are dealing therefore with a colloidal solution, and therefore with a solution of a body of very high molecular weight. We shall at the present moment, however, neglect other physical properties, for reasons which will be evident when we come to consider one of the first chemical properties to which a chemist generally turns his attention, viz., the property of functioning as an acid, base, or neutral body. We shall find, then, that it is possible to add minute quantities of alkali, or of acid, without destroying the original “ amphoteric ” character of the solution when tested with litmus paper. This property of functioning as a weak acid, or a weak base, is characteristic, as Cohnheim has pointed out in the case of the albumens, of those classes of bodies known as pseudo-acids and pseudo-bases. Our knowledge of these classes of bodies we
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