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116arsenic rcniovcd froiii thc spciss nre prcsent ns sulphides in the nlknlinc iiintte, and licnce dissolvc with ease. .Kcncc tlic rilknliiic innttc is simply ground nnrl transfcrrcd to nn iron tnuk of In most otlicr briiiichcs of precioiis iiictal vmclting, grcnt siiiiplicity csistv bccnusc of tlic high spccific griivity of tlic vnliiidh coustitntcnts ciisiiring t.licir sinking to tlic bottom of 1111 rnoltcn niiisscs. Tlic reiison why licrivy ~nctuls, such ns iridiuin, osiiiiuin, rliodiuni, ;uid rutlicniuni cun Lc skiuinicil off froin thc surfncc of lcntl is thnt tlicir rcspcctivc nrscniclcs nll posscss low spccific griivitics, bccnuse niucli iirsciiic is conibiiied.lt'liis inforinrrtion conld bc gleiincd from cnrly clicniiciil dictionnrics diiting back to iiiorc tlirin 11 ccntiiry ago, but priioticnl iipplicntion wiis not iii:iilc until 11'1 lciinin iised i t for gololclsniith's sweepings some 60 yc;irs ago. In n siiiiilnr ~nnnner, instciid of gold sinking t o the bottom of the inoltcn uinss when tlic spciss is treatcd with the nlkalinc fusion, it is converted to tlic coiiipnrntivcly light siilpliidc, unrl thus is rcniovcd in tlic top mattc.Tlrc rcpcutcd siilpliurizing rctliicctl tlic wliitc-inctal to II coriccntrntctl spciss rcImscntec1 by it fcw hundredweights containing ahout 4 oilnets of gold pcr cwt. Tbo :ilhlinc niuttc wliicli aiiiorilits to inii1iy tous in \wight, is rccluccd to nbout two-thirds of its \wight by subseqiicntly wasliiug with hot water. This rcdiiction is c!ntircly clcpcu~lcnt upon tiic rnt,io of &in, antiniony, and ;irscnic, to tlic insolublc bnsc nictnl s~~lpliidcs, iis tlic sodiutn sulphidc ruiiiuins solublc. l'hc proccss rcvcnls tlliit gold ciin bc rcnio\~ed froiii wliitc-mctnl or siiciss nlniost in its cntirety by npplying siiitnblo sulpliiirieiug.As with otlicr sulpliides, tlic filtration prcscnts sonic sniiill practicnl difliciilticu, unlcss n good typo of vncuiini filter is cmpioycd. 'l!lic bliick prccipitiitc which cousisb of gold sulphitlc, nntl snlpliidcs of thc otlicr biisc metnls, is c!asily dcnlt with by chilrgi1Ig on to ii siiiclting furnnce whcrc tho rcgulnr work of tlciiling with prccioiis nictnl " swccp " nnd residues is curried oet. Gold siilphide rcudilg piirts nitli its sulphrtr to coppcr, iron, nrirl other biuc iiictnls in niost smclting trcut.mcnts, iind i t is rcgiirtlctl as ~1 good siilpliiirizing ngcnt.A tenipcriiterc bclow 300" C. sufficcs to tlcconiposc gold siilpIiitlc into gold niid siilpbnr, nnd liciicc in gcucral smclting i t is not f o l d in tlic condition of sidphide. Sulpliur rcfiuing of gold dntcs bnclr to tlic clewnth ccntury \rhcn 11 description of the mctlrod wis witton Iiy Tlicopliilos, hiit tlic siilpiiurizing of spcias niore rc1:itctl to nickel nictiillurgy in eiirly yciirs, :iiitl in tlic foregoing iiistiincc t,lic sulphiir is usyd to collcct tlic gold. 'J'lic iniportniicc of tlic dlcct of thc originnl niicrobiologicd popiilntion of rnw fruit nintcrinl 011 tlic ultinintc product wries to R consiilcrnblc cstcnt nnd is lirrgcly ulfcctcid by t,lic ...

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No accurate stat.istics itre nviiilnble for the consuiiipbion of fruit drinks throughout tlic world, or iii tlic 1iiirro\ver confines of t.his countq-, but it. is ccrtaiii tliiit the totnl consumption of these I)c\-crages niiist now reiicli n COIOSS~I figure. 111 the lh-itish Isles, soft drinks iire iit present nliuost entirely iiinde from iniported juices sircli as orange, Icniou, nncl grape fruit, alt.liougli, RS will 1)e scwi in it later section, home-grown fruit is iiow l)cing ut,ilizccl for t,he production of ncrntctl juices. A most unfortunate fcnturc of tlie itidustry in so fnr :is it is concerned wit,Ii juices other tlinii those niiitle froin citrus fruits, is t,lie wick prevnleiicc of syiithctic flavours which beiir 1itt.k or no rcseml)lniice to the r e d fruit clmwter. Crucss' refers to the iinicricnn soft drink industry, which lint1 just experienced n phenonienul cspiiiision on nccount of t,lie int,roduction of prohibition, ns being iilniost cnt,irely synthetic iind as not utilizing iiny ;rppr~cinlh fraction of tlic vast quiintitics of soft fruits that were avnilablc for processing. Espcriencc indicates thut t,he position is siniilnr todiiy and tlint tlic nnt,urnl inntcriiil is rejected nnd its plitce tiiken by spurious iind syntlietic proclucts. This is by no nienns the cnse with citrus juices, where fruit Iliiitcriitl forms rit lcnst tltc basis of various foriiis of beverrrge. Shoulcl sojdiist.iciition with essences occur in tbcsc juices, it is inore tliiin probrible thiit the essences Iiave been cxtriictctl froni the peels and skins of the fruits, ant1 nctunlly itrc iis nirich fruit ninterinl ns the juices themselves.Citrus and other very ricitl juices must suflcr soiiic reduction in acidity previous to consumption. This is not geiiernlly nchieved by clieniiciil ncutruliziition of tlic organic acids, but by building up tlic juice with sugar into a syrup, cordial, or squash for subsequent, tliliit.ion. English fruit juices, nlt,liough not so iicid iis tlic citrus juices, are also much too sliarp for coiisiiniption in tlic fresh sttrte, nnd nre usunlly stored in the syrup stiite.Two juices iiloiie, amongst those of coiiimerciiil import-nnce, nre cupnble of being consuriied in tlte fresh stntc ufter suitnble blending. dpplc iind grtipc juices iire now being stored in u fresh coiitlition, \vitliout addition of sugur or reduction of ucidity, and ir quickly esj)iiiiding industry is being successful in producing inillioiis of gullolis of both types of juices in Ocr11iiiny, h s t r i i i , iiiid Switzerland.Four years ago, ~)itssioli fruit j uicc wrs introtliiccd into this country. Its recaptioil lins not bcc~i so overwhelming na wtis iwticiputcd, itor liiie this juice titktm the plncc of grape fruit 11s wtis being gcilcriilly cx1)cctctl. But its interesting cliiirnctcr hns ircliievctl for it ii t:crtuiii celebrity.It will thus be seen tliiit tlic juices fall into four distiiict classes iind they will be discussed in t,lie following sections :A. Citms juices B. Apple rind griipc juices C. Englisli soft frui...

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