Experimental morphology / by Charles Benedict Davenport.

  • Davenport, Charles Benedict, 1866-1944.
Date:
1897-99
Catalogue details

Licence: Public Domain Mark

Credit: Experimental morphology / by Charles Benedict Davenport. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    or by acting on the aldehydes, )c = 0 + H.s = ;c - s + H2O. It acts rather energetically upon algae and Infusoria. In Ver- tebrates, the central nervous system is attacked and the oxy- htemoglobin of the blood is altered. Sulphurous oxide (SOg) attacks members of the aldehyde group, — R\ E\ /SO3K )C = 0 + SO3KH = )C —OH H/ H/ \h aldehj'de. 0.1% kills lower fungi in a few minutes, 0.01% in a few hours. Selenous oxide (Se02), which acts chemically much like SOg and has a much greater molecular Aveight (64 : 111), acts less energetically as a poison. A 0.1% solution kills Spirogyra and Zygnema in 3 hours, while 0.01% is scarcely injurious. Tellurous oxide (Te02, mol. wt. = 157) is non-poisonous, although chemically closely allied to the two preceding. (BOKORNY, '93.) Aldehydes. — The poisonous action of these substances de- rived from oxidation of alcohol is dependent upon their insta- bility. So we find that an aldehyde, which, like grape sugar, is fairly stable, is likewise non-poisonous; while formaldehyde, which is very unstable and active, is correspondingly poisonous. Aldehydes attack especially the unstable amides, affording ni- trogenous compounds; e.g. — CfiH^ • NH2 + CH2O = CeHsNCHo + H2O. Now, even in passive albumens, part of the N is in the form of amido-groups; for, in treating with nitric acid, much nitro- gen is set free, which would not occur were all of the N second- arily or tertiarily bound up. (LoEW, '93, p. 58.) Hence the poisonousness of aldehydes for living albumens. Formaldehyde.—This substance (H — CH : O) acts upon propeptones and upon albumen, affording compounds which are not readily soluble. An aqueous solution of —