Part 5471

<note>&hand; Although a gas, hydrogen is chemically similar to the metals in its nature, having the properties of a weak base. It is, in all acids, the base which is replaced by metals and basic radicals to form salts. Like all other gases, it is condensed by great cold and pressure to a liquid which freezes and solidifies by its own evaporation. It is absorbed in large quantities by certain metals (esp. palladium), forming alloy-like compounds; hence, in view of quasi-metallic nature, it is sometimes called <altname>hydrogenium</altname>. It is the typical reducing agent, as opposed to oxidizers, as oxygen, chlorine, etc.</note>

<cs><col>Bicarbureted hydrogen</col>, <cd>an old name for ethylene.</cd> -- <col>Carbureted hydrogen gas</col>. <cd>See under <er>Carbureted</er>.</cd> -- <col>Hydrogen dioxide</col>, <cd>a thick, colorless liquid, <chform>H2O2</chform>, resembling water, but having a bitter, sour taste, produced by the action of acids on barium peroxide. It decomposes into water and oxygen, and is manufactured in large quantities for an oxidizing and bleaching agent. Called also <altname>oxygenated water</altname>.<-- usually "hydrogen peroxide", or "peroxide" in weak solutions used as an antiseptic--></cd> -- <col>Hydrogen oxide</col>, <cd>a chemical name for water, H<?/O.</cd> -- <col>Hydrogen sulphide</col>, <cd>a colorless inflammable gas, <chform>H2S</chform>, having the characteristic odor of bad eggs, and found in many mineral springs. It is produced by the action of acids on metallic sulphides, and is an important chemical reagent. Called also <altname>sulphureted hydrogen</altname>.</cd></cs>

<h1>Hydrogenate</h1> <Xpage=717>

<hw>Hy"dro*gen*ate</hw> <tt>(?)</tt>, <tt>v. t.</tt> <wordforms>[<tt>imp. & p. p.</tt> <er>Hydrogenated</er> <tt>(?)</tt>; <tt>p. pr. & vb. n.</tt> <er>Hydrogenating</er> <tt>(?)</tt>.]</wordforms> <fld>(Chem.)</fld> <def>To hydrogenize.</def>

<h1>Hydrogenation</h1> <Xpage=717>

<hw>Hy`dro*gen*a"tion</hw> <tt>(?)</tt>, <tt>n.</tt> <fld>(Chem.)</fld> <def>The act of combining with hydrogen, or the state of being so combined.</def>

<h1>Hydrogenide</h1> <Xpage=717>

<hw>Hy"dro*gen*ide</hw> <tt>(?)</tt>, <tt>n.</tt> <fld>(Chem.)</fld> <def>A binary compound containing hydrogen; a hydride. <mark>[R.]</mark> See <er>Hydride</er>.</def>

<h1>Hydrogenium</h1> <Xpage=717>

<hw>Hy`dro*ge"ni*um</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[NL. See <er>Hydrogen</er>.]</ety> <fld>(Chem.)</fld> <def>Hydrogen; -- called also in view of its supposed metallic nature.</def>

<i>Graham.</i>

<h1>Hydrogenize</h1> <Xpage=717>

<hw>Hy"dro*gen*ize</hw> <tt>(?)</tt>, <tt>v. t.</tt> <wordforms>[<tt>imp. & p. p.</tt> <er>Hydrogenized</er> <tt>(?)</tt>; <tt>p. pr. & vb. n.</tt> <er>Hydrogenizing</er> <tt>(?)</tt>.]</wordforms> <fld>(Chem.)</fld> <def>To combine with hydrogen; to treat with, or subject to the action of, hydrogen; to reduce; -- contrasted with <i>oxidize</i>.</def>

<h1>Hydrogenous</h1> <Xpage=717>

<hw>Hy*drog"e*nous</hw> <tt>(?)</tt>, <tt>a.</tt> <def>Of or pertaining to hydrogen; containing hydrogen.</def>

<h1>Hydrognosy</h1> <Xpage=717>

<hw>Hy*drog"no*sy</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[<ets>Hydro-</ets>, 1 + Gr. <?/ knowledge.]</ety> <def>A treatise upon, or a history and description of, the water of the earth.</def>

<h1>Hydrogode</h1> <Xpage=717>

<hw>Hy"drog*ode</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[<ets>Hydrog</ets>en + Gr. <?/ way. path.]</ety> <fld>(Elec.)</fld> <def>The negative pole or cathode.</def> <mark>[R.]</mark>

<h1>Hydrographer</h1> <Xpage=717>

<hw>Hy*drog"ra*pher</hw> <tt>(?)</tt>, <tt>n.</tt> <def>One skilled in the hydrography; one who surveys, or draws maps or charts of, the sea, lakes, or other waters, with the adjacent shores; one who describes the sea or other waters.</def>

<i>Boyle.</i>

<h1>Hydrographic, Hydrographical</h1> <Xpage=717>

<hw><hw>Hy`dro*graph"ic</hw> <tt>(?)</tt>, <hw>Hy`dro*graph"ic*al</hw> <tt>(?)</tt>,<hw> <tt>a.</tt> <def>Of or relating to hydrography.</def>

<h1>Hydrography</h1> <Xpage=717>

<hw>Hy*drog"ra*phy</hw> <tt>(?)</tt>, <tt>n.</tt> <ety>[<ets>Hydro-</ets>, 1 + -<ets>graphy</ets>: cf. F. <ets>hydrographie</ets>.]</ety> <p><b>1.</b> <def>The art of measuring and describing the sea, lakes, rivers, and other waters, with their phenomena.</def>

<p><b>2.</b> <def>That branch of surveying which embraces the determination of the contour of the bottom of a harbor or other sheet of water, the depth of soundings, the position of channels and shoals, with the construction of charts exhibiting these particulars.</def>

<h1>Hydroguret</h1> <Xpage=717>