A dictionary of terms used in medicine and the collateral sciences / by Richard D. Hoblyn.

  • Hoblyn, Richard D. (Richard Dennis), 1803-1886.
Date:
1878
Catalogue details

Licence: Public Domain Mark

Credit: A dictionary of terms used in medicine and the collateral sciences / by Richard D. Hoblyn. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    A CHROIA (u'xooia). A Hippocratic term denoting want of colour, loss of colour, paleness; opposed to tCxf'Oio, mcliroia, or good- ness of colour. The term is also ap|)lied to a colourless state of the skin depending upon a want of pigmentary matter of the rete mucosum. See Dyschroia. ACHROMATOTSIA («, priv., colour, vision). Want of power in distinguishing colours. See Chromaiodysopsia. ACrCULAR (acicula, a little needle). A term applied, in crystal- lography, to needle-shaped crystals; and, in botany, to the leaves of certain plants which are long, stiff, and pointed, like a needle; or to stafaces which are marked witli fine needle-like streaks. A'CID. An electro-negative compound which is capable of tmiting in definite ])roportions with alkaline bases, and which, when liquid or in a state of solution, has a sour taste, changes blue litmus to red, and restores to turmeric, previously changed brown by an alkali, its original yellow. An acid may be defined, with reference to its composition, as “ a liydrogenized body which can readily exchange its hydrogen for a metal.” It is a salt of hydrogen. 1. The Names of Acids, formed from the same base, vary in their lenninations, according to the quantity of oxygen which they arc pre- sumed to contain. Thus, Acids which terminate in -ic denote the maximum of oxidation ; in-07/.s, a lower proportion ; those which begin with hyper- (uTTip, above) denote an excess of oxidation ; with hypo- (vTTo, under), the lowest proportion. Sec Sal. 2. The Acids which terminate in -teform comjmunds wliich terminate in -ale ; those which terminate in -ous form compounds which tcnniui.tc in -ite; thus, sulphurtc acid forms salts which are called sulpha/e.v, while sulphuro«s acid forms salts which are called sulphtVc.v. 3. Aridifiable. A term applied to substances capable of being con- verted into an acid by an acidifying principle. Substances possessing this projicrty are called radicals, or acidifiahle bases. 4. Acidifywg Principle. That wliich possesses the property of con- verting a substance into an acid, (fxygen was formerly siqinosed to be the general acidifying principle of nature: no such general princii»le, however, exists. h. Acidi-metry (pt-Tpiut, to measure). The measurement of acids. The iirocess of determining, either by volumetric analisis, or by direct weighing, the amount of free acid contained in arid solutions. 6. Acidulous. Slightly acid ; a term applied to those salts in which the base is combined with such an excess of acid that they manifestly exhibit acid properties, as the supertartrate of potassa ; and to certain mineral waters wliich contain carbonic acid. ACI'DITAS KSURI'NA {esurire, to be huugrv'). A disease in which an excess of acid secretion in the stomach is capable of being nentrali'/.ed or absorbed by most of the substances eaten by persons alfccted with ]ura. A'CIDS, COUi’LKD. Organic acids which contain an acid coupled with another body, which docs not neutralize the acid, but accompanies it in all its combinations. Thus, in bydro-sulphuro-napbthalic acid, we have hydro-sulphuric acid coupled with naphthaline, and the coupled acid neutralizes exactly as muen base as the hydro-sulphuric acid alone would neutralize. ACINE'SIS (n, priv., Kivttx), to move). Akincsis. Paralysis of