See also:

• GUM (Fr. gomme, Lat. gommi, Gr. Kµµ1, possibly a Coptic word; distinguish " gum," the fleshy covering of the base of a tooth, in O. Eng. gbma, palate, cf. Ger. Gaumen, roof of the mouth; the ultimate origin is probably the root gha, to open wide, seen in

GUM (Fr. gomme, See also:

• LAT

Lat. gommi, Gr. Kµµ1, possibly a Coptic word; distinguish " gum," the fleshy covering of the See also:

• BASE

base of a tooth, in O. Eng. gbma, See also:

• PALATE (Lat. palatum, possibly from the root of pascere, to feed)

palate, cf. Ger. Gaumen, roof of the mouth; the ultimate origin is probably the See also:

• ROOT (late O.E. rot, adopted from Scand., cf. Norw. and Swed. rot, Dan. rod; the true O.E. word was wyrt, plant, represented in Ger. Wurz or Wurzel; the ultimate root is the same in both words, and is seen in Lat. radix)
• ROOT, ELIHU (1845– )

root gha, to open wide, seen in  Gr. xaivety, to gape, cf . "yawn"), the generic name given to a See also:

• GROUP

group of amorphous See also:

• CARBO

carbo-hydrates of the See also:

• GENERAL
• GENERAL (Lat. generalis, of or relating to a genus, kind or class)

general See also:

• FORMULA
• FORMULA (Lat. diminutive of forma, shape, pattern, &c., especially used of rules of judicial procedure)

formula (C5H1005),,, which exist in the juices of almost all See also:

• PLANTS

plants, and also occur as exudations from stems, branches and fruits of plants . They are entirely soluble or soften in See also:

• WATER

water, and See also:

• FORM (Lat. forma)

form with it a thick glutinous liquid or See also:

• MUCILAGE (from Late Lat. mucilago, a mouldy juice, from mucere, to be mouldy)

mucilage . They yield mucic and oxalic acids when treated with nitric See also:

• ACID (from the Lat. root ac-, sharp; acere, to be sour)

acid . In'structure the gums are quite amorphous, being neither organized like See also:

• STARCH

starch nor crystallized like See also:

• SUGAR

sugar . They are odourless and tasteless, and some yield clear aqueous solutions—the real gums—while others swell up and will not percolate See also:

• FILTER (a word common in various forms to most European languages, adapted from the medieval Lat. fi-ltrum, felt, a material used as a filtering agent)

filter See also:

• PAPER
• PAPER (Fr. papier, from Lat. papyrus)

paper—the See also:

• VEGETABLE

vegetable mucilages . The acacias and the See also:

• ROSACEAE

Rosaceae yield their gums most abundantly when sickly and in an abnormalstate, caused by a fulness of See also:

• SAP

sap in the See also:

• YOUNG
• YOUNG, A
• YOUNG, ARTHUR (1741-1820)
• YOUNG, BRIGHAM (1801-1877)
• YOUNG, CHARLES MAYNE (1777–1856)
• YOUNG, EDWARD (1683–1765)
• YOUNG, JAMES (1811-1883)
• YOUNG, THOMAS (1773-1829)

young tissues, whereby the new cells are softened and finally disorganized; the cavities thus formed fill with liquid, which exudes, dries and constitutes the See also:

• GUM (Fr. gomme, Lat. gommi, Gr. Kµµ1, possibly a Coptic word; distinguish " gum," the fleshy covering of the base of a tooth, in O. Eng. gbma, palate, cf. Ger. Gaumen, roof of the mouth; the ultimate origin is probably the root gha, to open wide, seen in

gum . Gum arabic may be taken as the type of the gums entirely soluble in water . Another variety, obtained from the Prosopis dulcis, a leguminous plant, is called gum See also:

• MESQUITE, or HONEY LOCUST

mesquite or mezquite; it comes from western See also:

• TEXAS

Texas and See also:

• MEXICO
• MEXICO (Span. Mejico, or Mexico,)
• MEXICO, FEDERAL DISTRICT OF
• MEXICO, GULF OF

Mexico, and is yellowish in See also:

• COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour, very brittle and quite soluble in water . Gum arabic occurs in pieces of varying See also:

• SIZE

size, and some kinds are full of See also:

• MINUTE
• MINUTE (Lat. minutes, small; minuere, to make less)

minute cracks . The specific gravity of See also:

• TURKEY

Turkey picked gum (the purest variety) is 1.487, or, when dried at too° C., 1.525 . It is soluble in water to an indefinite extent; boiled with dilute sulphuric acid it is converted into the sugar galactose .

Moderately strong nitric acid changes it into mucic, saccharic, tartaric and oxalic acids . Under the See also:

• INFLUENCE (Late Lat. influentia, from influere, to flow in)

influence of yeast it does not enter into the alcoholic See also:

• FERMENTATION

fermentation, but M . P . E . See also:

• BERTHELOT, MARCELLIN PIERRE EUGENE (1827–1907)

Berthelot, by digesting with See also:

• CHALK

chalk and See also:

• CHEESE (Lat. caseus)

cheese, obtained from it 12 % of its See also:

• WEIGHT

weight of See also:

• ALCOHOL

alcohol, along with See also:

• CALCIUM [symbol Ca, atomic weight 40.0 (o= x6)]

calcium lactate, but no appreciable quantity of sugar . Gum arabic may be regarded as a See also:

• POTASSIUM [symbol K (from kalium), atomic weight 39.114 0=16)]

potassium and calcium See also:

• SALT (a common Teutonic word, cf. Dutch zout, Ger. Salz, Scand. salt; cognate with Gr. &Xs, Lat. sal)
• SALT, SIR TITUS, BART

salt of gummic or arabic acid . T . See also:

• GRAHAM, SIR GERALD (1831–1899)
• GRAHAM, SIR JAMES ROBERT GEORGE
• GRAHAM, SYLVESTER (1794-1851)
• GRAHAM, THOMAS (1805-1869)

Graham (Chemical and See also:

• PHYSICAL

Physical Researches) recommended See also:

• DIALYSIS (from the Gr. &0., through, Anew, to loosen)

dialysis as the best mode of preparing gummic acid, and stated that the See also:

• POWER [WILLIAM GRATTAN] TYRONE (1797-1841)

power of gum to penetrate the See also:

• PARCHMENT

parchment septum is 400 times less than that of See also:

• SODIUM [symbol Na, from Lat. natrium; atomic weight 23.00 (0=16)]

sodium chloride, and, further, that by mixing the gum with substances of the crystalloid class the diffusibility is lowered, and may be even reduced to nothing . The mucilage must be acidulated with hydrochloric acid before dialysing, to set See also:

• FREE

free the gummic acid . By adding alcohol to the See also:

• SOLUTION (from Lat. solvere, to loosen, dissolve)

solution, the acid is precipitated as a See also:

• WHITE
• WHITE, ANDREW DICKSON (1832– )
• WHITE, GILBERT (1720–1793)
• WHITE, HENRY KIRKE (1785-1806)
• WHITE, HUGH LAWSON (1773-1840)
• WHITE, JOSEPH BLANCO (1775-1841)
• WHITE, RICHARD GRANT (1822-1885)
• WHITE, ROBERT (1645-1704)
• WHITE, SIR GEORGE STUART (1835– )
• WHITE, SIR THOMAS (1492-1567)
• WHITE, SIR WILLIAM ARTHUR (1824--1891)
• WHITE, SIR WILLIAM HENRY (1845– )
• WHITE, THOMAS (1628-1698)
• WHITE, THOMAS (c. 1550-1624)

white amorphous See also:

• MASS (O.E. maesse; Fr. messe; Ger. Messe; Ital. messa; from eccl. Lat. missa)
• MASS, IN

mass, which becomes glassy at too' . Its formula is (See also:

• C6H

C6H,005)2HSO, and it forms compounds with nearly all bases which are easily soluble in water . Gummic acid reddens See also:

• LITMUS (apparently a corruption of lacmus, Dutch lacmoes, lac, lac, and moes, pulp, due to association with " lit," an obsolete word for dye, colour; the Ger. equivalent is Lac/emus, Fr tournesol)

litmus, its re-See also:

• ACTION

action being about equal to carbonic acid .

When solutions of gum arabic and See also:

• GELATIN, or GELATINE

gelatin are mixed, oily drops of a See also:

• COMPOUND
• COMPOUND (from Lat. componere, to combine or put together)

compound of the two are precipitated, which on See also:

• STANDING

standing form a nearly colourless jelly, melting at 25° C., or by the See also:

• HEAT (0. E. haktu, which like " hot," Old Eng. hat, is from the Teutonic type haita, hit, to be hot; cf. Ger. hitze, heiss; Dutch, hitte, heet, &c.)

heat of the See also:

• HAND
• HAND (a word common to Teutonic languages; cf. Ger. Hand, Goth. handus)
• HAND, FERDINAND GOTTHELF (1786-185r)

hand . This substance can be washed without decomposition . Gummic acid is soluble in water; when well dried at See also:

• IOO

Ioo° C., it becomes transformed into metagummic acid, which is insoluble, but swells up in water like gum tragacanth . Gum arabic, when heated to 15o' C. with two parts of acetic anhydride, swells up to a mass which, when washed with boiling water, and then with alcohol, gives a white amorphous insoluble See also:

• POWDER (through O. Fr. puldre, modern poudre, from Lat. pulvis, pulveris, dust)

powder called acetyl arabin C6H8(C2H30)205 . It is saponified by alkalies, with See also:

• REPRODUCTION

reproduction of soluble gum . Gum arabic is not precipitated from solution by See also:

• ALUM

alum, stannous chloride, sulphate or nitrate of See also:

• COPPER (symbol Cu, atomic weight 63.1, H=1, or 63.6, O = 16)

copper, or neutral See also:

• LEAD
• LEAD (pronounced iced)

lead acetate; with basic lead acetate it forms a white jelly, with ferric chloride it yields a stiff clear gelatinoid mass, and its solutions are also precipitated by See also:

• BORAX (sodium pyroborate or sodium biborate)

borax . The finer varieties are used as an emollient and demulcent in See also:

• MEDICINE

medicine, and in the manufacture of See also:

• CONFECTIONERY (from Lat. confectio, conficere, compound)

confectionery; the commoner qualities are used as an adhesive See also:

• PASTE (O. Fr. paste, modern pate, Late Lat. pasta, whence also in Span., Port. and Ital., from Gr. 1r&vrrl or 1raara, barley porridge, or salted pottage, ir&ao'ety, to sprinkle with salt)

paste, for giving lustre to See also:

• CRAPE (an anglicized version of the Fr. crepe)

crape, See also:

• SILK

silk, &c., in See also:

• CLOTH

cloth See also:

• FINISHING

finishing to stiffen the See also:

• FIBRES
• FIBRES (or FIBERS, in American spelling; from Lat. fibra, apparently connected either with filum, thread, or findere, to split)

fibres, and in See also:

• CALICO

calico-See also:

• PRINTING (from Lat. imprimere, O. Fr. empreindre)

printing . For labels, &c., it is usual to mix sugar or See also:

• GLYCERIN, GLYCERINE

glycerin with it to prevent it from cracking . Gum See also:

• SENEGAL

senegal, a variety of gum arabic produced by See also:

• ACACIA

Acacia Verek, occurs in pieces generally rounded, of the size of a See also:

• PIGEON

pigeon's See also:

• EGG (O.E. aeg, cf. Ger. Ei, Swed. aegg, and prob. Gr. u,ov, Lat. ovum)
• EGG, AUGUSTUS LEOPOLD (1816-1863)

egg, and of a reddish or yellow colour, and specific gravity 1.436 . It gives with water a somewhat stronger mucilage than gum arabic, from which it is distinguished by its clear interior, fewer cracks and greater toughness . It is imported from the See also:

• RIVER

river See also:

• GAMBIA

Gambia, and from Senegal and See also:

• BATHURST
• BATHURST, EARLS

Bathurst . Chagual gum, a variety brought from See also:

• SANTIAGO, or SANTIAGO DE CHILE

Santiago, See also:

• CHILE, or CHILI (derived, it is said, from the Quichua chin , cold, or tchili, snow)

Chile, resembles gum senegal .

About 75% is soluble in water . Its solution is not thickened by borax, and is precipitated by neutral lead acetate; and dilute sulphuric acid converts it into d-See also:

• GLUCOSE (from Gr. - twais, sweet)

glucose . Gum tragacanth, familiarly called gum See also:

• DRAGON (Fr. dragon, through Lat. draco, from the Greek; connected with SEpeoµay " see," and interpreted as " sharp-sighted "; O.H. Ger. tracho, dracho, M.H.G. trache, Mod. Ger. Drachen; A.S. draca, hence the equivalent English form " drake," " fire-drake,

dragon, exudes from the See also:

• STEM (O. Eng. staefn, stemn, cf. Du. stain, Ger. Stamm, &c., probably related to " staff ")

stem, the See also:

• LOWER

lower See also:

• PART

part especially, of the various See also:

• SPECIES

species of Astragalus, especially A. gummifer, and is collected in See also:

• ASIA

Asia See also:

• MINOR
• MINOR (Lat. for smaller, lesser)
• MINOR, ROBERT CRANNELL (1839-1904)

Minor, the See also:

• CHIEF (from Fr. chef, head, Lat. caput)

chief See also:

• PORT

port of shipment being See also:

• SMYRNA (Ismir)

Smyrna . Formerly only what exuded spontaneously was gathered; this was often of a brownish colour; but now the flow of the gum is aided by incisions cut near the See also:

• ROOT (late O.E. rot, adopted from Scand., cf. Norw. and Swed. rot, Dan. rod; the true O.E. word was wyrt, plant, represented in Ger. Wurz or Wurzel; the ultimate root is the same in both words, and is seen in Lat. radix)
• ROOT, ELIHU (1845– )

root, and the product is the See also:

• FINE

fine, white, flaky variety so much valued in See also:

• COMMERCE
• COMMERCE (Lat. commercium, from, cum, together, and rnerx, merchandise)

commerce . The chief flow of gum takes See also:

• PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place during the See also:

• NIGHT

night, and hot and dry See also:

• WEATHER (O. Eng. weder; the word is common to Teutonic languages; cf. Du. weder, Dan. veir, Icel. ve8r, and Ger. Wetter and Gewitter, storm; the root is wa- to blow, from which is derived " wind ")

weather is the most favourable for its See also:

• PRODUCTION (Lat. productionem, from producere, to pro-duce)

production . In colour gum tragacanth is of a dull white; it occurs in horny, flexible and tough, thin, See also:

• TWISTED

twisted flakes, translucent, and with See also:

• PECULIAR

peculiar wavy lines on the See also:

• SURFACE

surface . When dried at temperatures under too° C. it loses about 14% of water, and is then easily powdered . Its specific gravity is 1.384 . With water it swells by absorption, and 716 with even fifty times its weight of that liquid forms a thick mucilage . Part of it only is soluble in water, and that resembles gummic acid in being precipitated by alcohol and ammonium oxalate, but differs from it in giving a precipitate with neutral lead acetate and none with borax . The insoluble part of the gum is a calcium salt of bassorin (C12H200,o), which is devoid of See also:

• TASTE (from Lat. taxare, to touch sharply; tangere, to touch)

taste and See also:

• SMELL (connected etymologically with " smoulder " and " smoke ")

smell, forms a gelatinoid mass with water, but by continued boiling is rendered soluble . Gum tragacanth is used in calico-printing as a thickener of See also:

• COLOURS, MILITARY

colours and mordants; in medicine as a demulcent and vehicle for insoluble powders, and as an excipient in pills; and for setting and mending beetles and other See also:

• INSECT

insect specimens .

It is medicinally See also:

• SUPERIOR

superior to gum acacia, as it does not undergo acetous fermentation . The best pharmacopeial preparation is the Mucilago Tragacanthae . The compound powder is a useless preparation, as the starch it contains is very liable to ferment . Gum kuteera resembles in See also:

• APPEARANCE (from Lat. apparere, to appear)

appearance gum tragacanth, for which the See also:

• ATTEMPT (Lat. adtemptare, attentare, to try)

attempt has occasionally been made to substitute it . It is said to be the product of Sterculia urens, a plant of the natural See also:

• ORDER
• ORDER (through Fr. ordre, for earlier ordene, from Lat. ordo, ordinis, rank, service, arrangement; the ultimate source is generally taken to be the root seen in Lat. oriri, rise, arise, begin; cf. " origin ")
• ORDER, HOLY

order Sterculiaceae . See also:

• CHERRY

Cherry See also:

• TREE (0. Eng. treo, treow, cf. Dan. tree, Swed. Odd, tree, trd, timber; allied forms are found in Russ. drevo, Gr. opus, oak, and 36pv, spear, Welsh derw, Irish darog, oak, and Skr. dare, wood)
• TREE, SIR HERBERT BEERBOHM (1853- )

tree gum is an exudation from trees of the genera Prunus and Cerasus . It occurs in shiny reddish lumps, resembling the commoner kinds of gum arabic . With water, in which it is only partially soluble, it forms a thick mucilage . Sulphuric acid converts it into l-arabinose; and nitric acid oxidizes it to oxalic acid (without the intermediate formation of mucic acid as in the See also:

• CASE
• CASE, JOHN (d. 1600)

case of gum arabic) . Gum of Bassora, from Bassora or Bussorah in Asia, is some-times imported into the See also:

• LONDON

London See also:

• MARKET (Lat. mercatus, trade or place of trade)

market under the name of the hog tragacanth . It is insipid, crackles between the See also:

• TEETH (O.E. Eel); plural of tooth, O.E. top)

teeth, occurs in variable-sized pieces, is tough, of a yellowish-white colour, and opaque, and has properties similar to gum tragacanth . Its specific gravity is 1.36 .

It contains only 1% of soluble gum or arabin . Under the name of Caramania gum it is mixed with inferior kinds of gum tragacanth before exportation . Mucilage.—Very many seeds, roots, &c., when infused in boiling water, yield mucilages which, for the most part, consist of bassorin . See also:

• LINSEED

Linseed, See also:

• QUINCE (Lat. Cydonia or Colonea, Ital. Cotogna, Fr. coing, Mid. Eng. coin, quiet, whence a collective plural " quins," corrupted to singular " quince ")

quince See also:

• SEED (from the root seen in Lat. serere, to sow)

seed and marshmallow root yield it in large quantity . In their reactions the different kinds of mucilage See also:

• PRESENT

present See also:

• DIFFERENCES, CALCULUS OF (Theory of Finite Differences)

differences; e.g. quince seed yields only oxalic acid when treated with nitric acid, and with a solution of See also:

• IODINE (symbol I, atomic weight '26.92)

iodine in See also:

• ZINC

zinc iodide it gives, after some See also:

• TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
• TIME, MEASUREMENT OF
• TIME, STANDARD

time, a beautiful red tint . Linseed does not give the latter reaction; by treatment with boiling nitric acid it yields mucic and oxalic acids . Gum Resins.—This See also:

• TERM

term is applied to the inspissated milky juices of certain plants. which consist of gum soluble in water, See also:

• RESIN (through O.Fr. resine, modern reline, from Lat. resina, prcbably Latinized from Greek Pirivrt, resin)

resin and essential oil soluble in alcohol, other vegetable See also:

• MATTER

matter and a small amount of See also:

• MINERAL

mineral matter . They are generally opaque and solid, and often brittle . When finely powdered and rubbed down with water they form emulsions, the undissolved resin being suspended in the gum solution . Their chief uses are in medicine . Examples are See also:

• AMMONIACUM, or GUM AMMONIAC

ammoniacum, asafetida, See also:

• BDELLIUM (0b XXwov, used by Pliny and Dioscorides as the 'name of a plant which exuded a fragrant gum)

bdellium, See also:

• EUPHORBIUM

euphorbium, See also:

• GAMBOGE (from Camboja, a name of the district whence it is obtained)

gamboge, See also:

• MYRRH (from the Latinized form myrrha of Gr. µuppa; the Arabic murr, bitter, was applied to the substance from its bitterness)

myrrh, sagapanum and See also:

• SCAMMONY

scammony .