Part 1840

<hw>Chem"ist</hw>, <tt>n.</tt> <ety>[Shortened from <ets>alchemist</ets>; cf. F. <ets>chimiste</ets>.]</ety> <def>A person versed in chemistry or given to chemical investigation; an analyst; a maker or seller of chemicals or drugs.</def>

<h1>Chemistry</h1> <Xpage=245>

<hw>Chem"is*try</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[From <er>Chemist</er>. See <er>Alchemy</er>.]</ety> <p><b>1.</b> <def>That branch of science which treats of the composition of substances, and of the changes which they undergo in consequence of alterations in the constitution of the molecules, which depend upon variations of the number, kind, or mode of arrangement, of the constituent atoms. These atoms are not assumed to be indivisible, but merely the finest grade of subdivision hitherto attained. Chemistry deals with the changes in the composition and constitution of molecules. See <er>Atom</er>, <er>Molecule</er>.</def>

<note>&hand; Historically, chemistry is an outgrowth of alchemy (or alchemistry), with which it was anciently identified.</note>

<p><b>2.</b> <def>An application of chemical theory and method to the consideration of some particular subject; <as>as, the <ex>chemistry</ex> of iron; the <ex>chemistry</ex> of indigo.</as></def>

<p><b>3.</b> <def>A treatise on chemistry.</def>

<note>&hand; This word and its derivatives were formerly written with <i>y</i>, and sometimes with i, instead of <i>e</i>, in the first syllable, <i>chymistry</i>, <i>chymist</i>, <i>chymical</i>, etc., or <i>chimistry</i>, <i>chimist</i>, <i>chimical</i>, etc.; and the pronunciation was conformed to the orthography.</note>

<cs><col>Inorganic chemistry</col>, <cd>that which treats of inorganic or mineral substances.</cd> -- <col>Organic chemistry</col>, <cd>that which treats of the substances which from the structure of organized beings and their products, whether animal or vegetable; -- called also <altname>chemistry of the carbon compounds</altname>. There is no fundamental difference between organic and inorganic chemistry.</cd> -- <col>Physiological chemistry</col>, <cd>the chemistry of the organs and tissues of the body, and of the various physiological processes incident to life.</cd> -- <mcol><col>Practical chemistry</col>, or <col>Applied chemistry</col></mcol>, <cd>that which treats of the modes of manufacturing the products of chemistry that are useful in the arts, of their applications to economical purposes, and of the conditions essential to their best use.</cd> -- <col>Pure chemistry</col>, <cd>the consideration of the facts and theories of chemistry in their purely scientific relations, without necessary reference to their practical applications or mere utility.</cd></cs>

<h1>Chemitype</h1> <Xpage=245>

<hw>Chem"i*type</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[<ets>Chemi</ets>cal + <ets>-type</ets>.]</ety> <fld>(Engraving)</fld> <def>One of a number of processes by which an impression from an engraved plate is obtained in relief, to be used for printing on an ordinary printing press.</def>

<h1>Chemolysis</h1> <Xpage=245>

<hw>Che*mol"y*sis</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[<ets>Chemi</ets>cal + Gr. <?/ a loosing.]</ety> <def>A term sometimes applied to the decomposition of organic substance into more simple bodies, by the use of chemical agents alone.</def>

<i>Thudichum.</i>

<h1>Chemosmosis</h1> <Xpage=245>

<hw>Chem`os*mo"sis</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[<ets>Chemi</ets>cal + <ets>osmosis</ets>.]</ety> <def>Chemical action taking place through an intervening membrane.</def>

<h1>Chemosmotic</h1> <Xpage=245>

<hw>Chem`os*mot"ic</hw> <tt>(?)</tt>, <tt>a.</tt> <def>Pertaining to, or produced by, chemosmosis.</def> <mark>[R.]</mark>

<h1>Chemung period</h1> <Xpage=245>

<hw>Che*mung" pe"ri*od</hw> <tt>(?)</tt>, <fld>(Geol.)</fld> <def>A subdivision in the upper part of the Devonian system in America, so named from the Chemung River, along which the rocks are well developed. It includes the Portage and Chemung groups or epochs. See the Diagram under <er>Geology</er>.</def>

<h1>Cheng</h1> <Xpage=245>

<hw>Cheng</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[Chinese.]</ety> <def>A chinese reed instrument, with tubes, blown by the mouth.</def>

<h1>Chenille</h1> <Xpage=245>

<hw>Che*nille"</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[F., prop., a caterpillar.]</ety> <def>Tufted cord, of silk or worsted, for the trimimg of ladies' dresses, for embroidery and fringes, and for the weft of chenille rugs.</def>

<h1>Chenomorph\'91</h1> <Xpage=245>

<hw>Che`no*mor"ph\'91</hw> <tt>(?)</tt>, <tt>n.</tt>; <plu>pl.</plu> <ety>[NL., from Gr. <?/ the wild goose + <?/ form.]</ety> <fld>(Zo\'94l.)</fld> <def>An order of birds, including the swans, ducks, geese, flamingoes and screamers.</def>

<h1>Chepster</h1> <Xpage=245>

<hw>Chep"ster</hw> <tt>(?)</tt>, <tt>n.</tt> <fld>(Zo\'94l.)</fld> <def>The European starling.</def> <mark>[Local, Eng.]</mark>

<h1>Cheque</h1> <Xpage=245>