MERCANTILISM. 330 MERCENARIES. that found in .Sir .Jaiiie^ Stoiuut's Inquiry into the Frinciples of I'olitical Economy (London. 1707). For the older critical attitude toward nieroantilism, consult Adam .Smith, Wealth of Nations, book iv. By far the best statement of the modern view is Sehmoller's Mercantile tiys- lem (Eng. trans., New York, 189C). MERCAP'TANS (from Lat. mercurius. mer- cury. (|ii(k>ilvi'r + ciiplans, prcs. part, of cap- tare, frciiiiciitativc of eapere, lo take; so called as al)s()rbin<; mercury). A class of carliiin com- pounds anal(ij;ous to the alcohols. The latter arc de(incd as eoiM|ic)uiids containing' one or inure (JIl (hydroxyl) ^;roups directly coml)ined with hyilro- carbon ■,'roups like nietliyl (CH3), ethyl (C.Hj), etc. Similarly, the niercaptans may be defined as compounds containini; one or more Sil (sulphur and hydroj^en) prouiis directly combined with hydrocarbon groups. Thus, methyl alcolud has the constitution ('11,011. metliyl mcrcajitan the constitution t'lljSIl: ethyl alcoliol has the consti- tution CjlI;.OII, ethyl nicr<apt:in the constitu- tion CJlsSll: etc. The following are the two principal methods used in preparing niercaptans: (1) by the action of an alcoholic solution of potassium sulpho-hvdrate (KSH) upon halogen derivatives of the hydrocarbons (CH3CI, C,H,C1, etc.); (2) by distilling an aqueous scdution of potassium sulpho-hydrate with salts of acids like the well-known cthyl-sul])huric acid. Thus methyl mercaptan may lie ])rcparcd according to either of the following reactions: I. CH,C1 -f KSH = CH,SH + KCl. Metliyl Potassium Methyl PotasMiiim chloride saiphn- mercaptan chloride hydrate /OCH, II. SOj + KSH = CH3SH + KjSOi K PotnHHium Potassium Methyl Potassium methyl- sulplio- mercaptan sulphate sulphate hydrate Most mercaptnns are liquid, though some exist, at ordinary temperatures, in the solid state. The liquid mcnaplans arc much more volatile than the corresponding alcohols. They are only spar- ingly soluble in water, but mix freely with alco- hol or ether. Their most eliaracteristic property, liowever, is their exceedingly ollcnsive odor, by which, according to Kniil Fischer and Pcnzoldt, a quantity of ethyl mercaptan can be detected that is 2.'i0 limes more minute than the smallest amount of sodium that can be revealed by the spectrosco])e. 'Hie hydrogen of the SIT group of a nu'rcaptan can he replaced by metals. The resulting substances, called 'merca|)tides,' arc de- composed by acids, but — unlike the alcoholates (see A1.COII01.S) — they are unalTectcd by pure water. The ethyl mcrcaptide of mercury is formed acconling to the following equation: 20,H,SH + TIgO = (C.n,8),Hg + H.O Ethyl M*'nMiric Mercuric Water mercaptan oxide inerctiptide The first mercaptan ever prepared was ethyl mer- captan, which was obtained liy Zeise in S3^. It is now extensively used in the manufacture of Bulphonal (q.v.), a well-known hypnotic. MERCAP'TIDES. See AIehcaptans. MERCA'TOR, Cicit.Muns (T.atinizcd form of Okrhahi) K11KMKII) (l.')12-n4). . Klemish niathe- inaticinn ami geographer, born in Rupelmonde, He took his degree in philosophy at the Univer- sity of Louvain, and later made a profound study of the sciences of geography and mathe- matics. In 1559 he was a|)pointed eosmographer to the Duke of .Jiilich and t'leves. His name in perpetuated by the projection used in nautical maps, in which the meridians are represented by parallel lines, and parallels of latitude by straight lines intersecting tlie meridians at right angles. Tlie projection, liowever, seems to have been applii'd to nautical maps by Edward Wright. Besides a large number of maps, Mercator com- piled series of geographical tallies. Tabula' (reo- f/raphiew ad Mentcm I'tolemai Uestituiw (1578). He also wrote a Uarmonia Ecungeliorum (1592); and a work entitled Atlas, give Cos- moffrui>hic<c ilcditaliones de Fabrica MutuU (159-I), which was placed on the Index Expurga- torius. MERCATOR (properly Kai'fmanx). Nico- LAU.s {c.l(i20-S7 ) . A (ierman mjithcmatician, astronomer, and engineer, born at t'ismar in the 1 Duchy of Ilolstein. He was e<lucated at the j universities of Copenhagen and Kostock. and in ■h 1000 or thereabouts went to London, where he became one of the first members of the Royal So- ciety, then newly founded. Subsequently he pro- ceeded to France, where he was :ip|ioiiiled hy- draulic engineer to direct the construction of the ^'ersailles fountains. Owing to his refusal to ac- cept the Roman Catholic faith, the sum agreed upon as payment for this work was withheld, and this fact is said to have hastened his death. He is credited with the discovery of several methods of calculation, in astronomy and higher mathe- matics. His publications include, besides con- tributions to the Philosophical Tran.<iactions ol the Royal Society. Cosmntfraphia (IGol); As- tronomia Sphwrica (1051); I'ationcs Mathe- malicw f^uhductd' (105;!); and Lofiarithmo- tcehnia (1008-74). Consult: Kacstner. dischichle dcr Matlwmatik (Gottingen, 1790-1800) ; Mon- tucla. Uistoire des mathfmatiques (Paris, 1799- 1802). MERCATOR'S PROJECTION. See CnABTj .Map: JIkimakih. (;iaiAUiils; N'AVUiATlo.N ; SaIL- l.N(iS. MERCEDES, mer-sii'Di'is. A tow n in the Prov- inii' of Hucnos Ayrcs. Argentina, situated on the I'acilic Railroad, .'50 miles west of Buenos Ayree (Map: Argentina. F 10). It is a flourishing town in a rich sheep-raising region, has a col- lege, a public library, and several steam-mills and soap factories. Population, about 10,000. It was founded a- a niilitjiry station in 1779, and has been settled largely by Irish immigrants. MERCENARIES (Lat. mcrccnarius, hireling, from I/O rcis. wage-;, from wcrcrr, to gain, de- serve; connected with Ok. fitipiadai, ini irrstliai, to share, divide). Hired .soldiers, usually for- eigners in the country for which they light. They existed from the earliest times. In the early (Jreek rejiublies there was no standing army or mercenary force, but the citizens them- selves formed a national militia. In Persia, how- ever, there were large numbers of Orcck merce- naries, and they aiii)ear to have played the same jiart which in later centuries the Swiss did in Western Europe. The first Orecian State which used mercenaries in large numbers was .tbens, and other Greek States soon followed this example, so that by the end of the Pelopon- nesian War there were a large number of men in
