SODIUM 



SODOM AND GOMORRAH 555 



j + 10H 2 O, has been already described under 

 its synonym of Glauber's Salt (q.v.). The acid 

 salt, or bisulphate of soda, NaHSO 4 , is of no special 

 interest. 



The Hyposulphite of Soda, NajS.,O 3 5H 2 O, occurs 

 in large colourless, striated, rhombic prisms, of a 

 cooling and sweet taste. When strongly heated 

 in the air it burns with a blue flame. It dissolves 

 readily in water, depositing sulphur if the solution 

 be kept in a closed vessel. It may be obtained by 

 digesting a solution of sulphite of soda with pow- 

 dered sulphur. The sulphur is gradually dissolved, 

 and forms a colourless solution, which, on evapora- 

 tion, yields crystals of hyposulphite of soda. This 

 salt is largely employed in photography, and is 

 occasionally prescribed medicinally. Sulphurous 

 acid forms two salts with soda viz. a sulphite and 

 a bisulphite. The Sulphite of Soda, NaHSO 3 + 

 7H.O, is obtained by passing sulphurous acid over 

 carbonate of soda, dissolving the resulting mass 

 in water, and crystallising ; when the salt is 

 obtained in efflorescent oblique prisms, which 

 are soluble in 4 parts of cold water, the solu- 

 tion having a slightly alkaline reaction and a 

 sulphurous taste. This compound was at one time 

 commercially known as Antichlore, and was largely 

 used in paper-manufactories for the purpose of 

 removing the last trace of chlorine from the 

 bleacheu rag pulp. The term is now applied only 

 to the hyposulphite, which is both cheaper and 

 more efficacious. The Bisulphite is of no import- 

 ance. Nitrate of Soda, NaNO 3 , known also as 

 Cubic Nitre or Chili Saltpetre, occurs as a natural 

 product on the surface of the soil of certain South 

 American districts. In most of its properties, 

 excepting its crystalline form, and further in its 

 being deliquescent, it resembles nitrate of potash. 

 It is used as a Manure (q.v.). The Phosphates of 

 Soda are comparatively numerous, Hypo-chlor- 

 ite of Soda, NaCIO, is at present known only in 

 solution, in which it occurs as a yellowish -green 

 fluid, evolving a smell of chlorine ; it has strong 

 bleaching power, and when boiled becomes de- 

 colorised, and evolves chlorine freely. It is formed 

 by passing a stream of chlorine gas through a solu- 

 tion of carbonate of soda, the resulting solution 

 containing the hypochlorite, together with unde- 

 composed carbonate of soda and chloride of sodium. 

 This solution is useful as a bleaching agent, as an 

 oxidising agent in analytical chemistry, and as a 

 disinfectant agent. There are two Borates of Soda, 

 of which the only important one, the Biborate, is 

 already described under its ordinary name of Borax 

 ( q. v. ). Various Silicates of Soda have been formed 

 (see SILICON, GLASS, SLAGS). 



The Haloid Salts of sodium resemble, in their 

 general characters, the corresponding salts of 

 potash. Of these by far the most important is 

 Chloride of Sodium, or Common Salt, formerly 

 known as Muriate of Soda, NaCl. It occurs natur- 

 ally in far greater quantity than any other soluble 

 salt, and is fully described at SALT. The other 

 haloid salts the iodide, bromide, and fluoride of 

 sodium require no notice. 



Sodium has been recently found to enter into 

 various groups of organic bodies the sodium- 

 alcohols for example. When sodium or potassium 

 is gradually added to anhydrous alcohol the tem- 

 perature rapidly rises, the metal is dissolved, hydro- 

 gen is evolved, and a fusible deliquescent compound 

 is formed, which has received the name of Sodium- 

 alcohol ( or potassium-alcohol ), or of ethylate of soda 

 (or potash), its composition being such that it may 

 be regarded as alcohol in which one atom of hydro- 

 gen is replaced by one of the metal. 



The tests for the salts of sodium are not very 

 satisfactory, because the metal forms scarcely any 

 insoluble compounds. A salt of sodium is usually 



concluded to be present when, the absence of all 

 other bases having been proved, a saline residue 

 remains, which, with bichloride of platinum, yields 

 yellow striated prisms by spontaneous evaporation. 

 Before the blowpipe the salts of sodium are known 

 by the intense yellow which they communicate to 

 the outer flame, and if a weak alcoholic solution of 

 one of the salts is burned a similar yellow tint is 

 communicated to the flame. Spectrum analysis is 

 too delicate to be of much practical use. 



The medicinal uses of the sodium compounds 

 may be considered alphabetically. Acetate of Soda 

 is a mild diuretic, similar in operation to acetate 

 of potash, for which it may be substituted. Ar- 

 seniate of Soda is serviceable in periodic affections, 

 chronic skin diseases, and the cases in which 

 arsenic is generally employed in medicine. Paper 

 impregnated with a solution of arseniate of soda 

 sweetened with sugar is sold as a poison for flies. 

 Biborate of Soda, or Borax, is employed principally 

 as a topical astringent, and is used with advantage 

 in aphthous eruptions of the mouth and throat. 

 Bicarbonate of Soda is a most popular remedy in 

 cases of dyspepsia, but its use is highly injurious 

 when there are phosphatic deposits in the urine. 

 Carbonate of Soda is not employed as an antacid so 

 frequently as the bicarbonate, in consequence of its 

 disagreeable taste ; but in the dried state, when 

 deprived by heat of its water of crystallisation, it 

 is much used as an alterative. In dyspepsia 

 attended with acidity a combination of the dried 

 carbonate with blue pill and rhubarb pill is often 

 extremely useful. As it has a very acrid taste, 

 it should be combined, if given in powder, with 

 some bland substance, such as Compound Traga- 

 canth Powder. A solution of Chlorinated Soda is 

 preferable to hypochlorite of lime in destroying 

 noxious effluvia, as the salt which is left does not 

 deliquesce. Phosphate of Soda, known also as 

 Tasteless Purging Salt, is a mild saline purgative, 

 with a far less unpleasant taste than sulphate of 

 magnesia. Sulphate of Soda and Tartrate of Soda 

 and Potash have been already described under 

 their ordinary names of Glauber's Salt (q.v.) and 

 Rochelle Salt (q.v.). 



Sodom. APPLE OF, the name given to the 

 fruit of a species of Solanum (q.v.). But it is 

 possible that the true Apple of Sodom, or Mad 

 Apple, of the shores of the Dead Sea, mentioned 

 by Strabo, Tacitus, and Josephus, and described 

 as beautiful to the eye, but filling the mouth with 

 bitter ashes if tasted, is a kind of gall growing on 

 dwarf oaks, and produced by a species of gall- 

 insect. 



Sodom and Gomorrah, two ancient cities, 

 almost invariably spoken of in conjunction in the 

 Bible, and forming with Admah, Zeboiim, and 

 other towns the 'cities of the plain," which, on 

 account of the enormous wickedness of their in- 

 habitants (the nature of which is indicated in the 

 term Sodomy ), are said to have been overthrown 

 not submerged by some terrible convulsion of 

 nature. Modern writers on sacred topography are 

 not agreed as to the site to be assigned to these 

 cities. It used to be generally held that they 

 stood on the southern shore of the Dead Sea, near 

 the salt ridge of Usdom (a form of the word 

 ' Sodom ' ). Conder believes, however, that he can 

 fix the site of Zoar, at least, at the foot of the 

 mountains of Moab, to the north-east of the Dead 

 Sea (q.v.). The popular belief that the cities were 

 miraculously overwhelmed by the waters of the 

 Dead Sea, and that their remains may still be 

 seen at the bottom, is an idle tale of superstitious 

 travellers, uncountenanced either by fact or by 

 the terms employed by Scripture to describe the 

 catastrophe. 



