Thesamerestrictionsalikeaffectedtheoperationsoftheglassmanufacture，which，withtheaidofforeignartisans，hadbeengraduallyestablishedinEngland，andwasbecomingathrivingbranchoftrade。Itwasevenproposedthatthesmeltingofironshouldbeabsolutelyprohibited：”manythink，”saidacontemporarywriter，”thatthereshouldbeNOWORKSANYWHERE——theydosodevourthewoods。”
Theuseofiron，however，couldnotbedispensedwith。Theveryfoundationsofsocietyresteduponanabundantsupplyofit，fortoolsandimplementsofpeace，aswellasforweaponsofwar。Inthedearthofthearticleathome，asupplyofitwasthereforesoughtforabroad；andbothironandsteelcametobeimportedinlargely-increasedquantities。ThisbranchoftradewasprincipallyinthehandsoftheSteelyardCompanyofForeignMerchants，establishedinUpperThamesStreet，alittleaboveLondonBridge；andtheyimportedlargequantitiesofironandsteelfromforeigncountries，principallyfromSweden，Germany，andSpain。ThebestironcamefromSpain，thoughtheSpaniardsontheirpartcovetedourEnglishmadecannons，whichwerebettermanufacturedthantheirs；whilethebeststeelcamefromGermanyandSweden。*
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Aslateas1790，longafterthemonopolyoftheforeignmerchantshadbeenabolished，Pennantsays，”ThepresentSteelyardisthegreatrepositoryofimportediron，whichfurnishesourmetropoliswiththatnecessarymaterial。Thequantityofbarsthatfillstheyardsandwarehousesofthisquarterstrikeswithastonishmentthemostindifferentbeholder。”——PENNANT，AccountofLondon，309。
Underthesecircumstances，itwasnaturalthatpersonsinterestedintheEnglishironmanufactureshouldturntheirattentiontosomeotherdescriptionoffuelwhichshouldserveasasubstitutefortheprohibitedarticle。Therewasknowntobeanabundanceofcoalinthenorthernandmidlandcounties，anditoccurredtosomespeculatorsmorethanusuallydaring，toproposeitasasubstituteforthecharcoalfuelmadefromwood。Butthesamepopularprejudicewhichexistedagainsttheuseofcoalfordomesticpurposes，preventeditsbeingemployedforpurposesofmanufacture；andtheywerethoughtveryfoolishpersonsindeedwhofirstpromulgatedtheideaofsmeltingironbymeansofpit-coal。Theoldmanufacturersheldittobeimpossibletoreducetheoreinanyotherwaythanbymeansofcharcoalofwood。Itwasonlywhenthewoodintheneighbourhoodoftheironworkshadbeenalmostentirelyburntup，thatthemanufacturersweredriventoentertaintheideaofusingcoalasasubstitute；butmorethanahundredyearspassedbeforethepracticeofsmeltingironbyitsmeansbecamegeneral。
ThefirstwhotookoutapatentforthepurposewasoneSimonSturtevant，aGermanskilledinminingoperations；theprofessedobjectofhisinventionbeing”toneale，melt，andworkeallkindofmetaloares，irons，andsteeleswithsea-coale，pit-coale，earth-coale，andbrushfewell。”Theprincipalendofhisinvention，hestatesinhisTreatiseofMetallica，*
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STURTEVANT’SMetallica；brieflycomprehendingtheDoctrineofDiverseNewMetallicalInventions，&c。ReprintedandpublishedattheGreatSealPatentOffice，1858。
istosavetheconsumptionandwasteofthewoodsandtimberofthecountry；and，shouldhisdesignsucceed，heholdsthatit”willprovetobethebestandmostprofitablebusinessandinventionthateverwasknownorinventedinEnglandthesemanyyeares。”Hesayshehasalreadymadetrialoftheprocessonasmallscale，andisconfidentthatitwillproveequallysuccessfulonalargeone。Sturtevantwasnotveryspecificastohisprocess；butitincidentallyappearstohavebeenhispurposetoreducethecoalbyanimperfectcombustiontotheconditionofcoke，therebyriddingitof”thosemalignantproprietieswhichareaversetothenatureofmetalliquesubstances。”
Thesubjectwastreatedbyhim，aswascustomaryinthosedays，asagreatmystery，madestillmoremysteriousbythemultitudeoflearnedwordsunderwhichheundertooktodescribehis”IgnickInvention”Alltheoperationsofindustrywerethentreatedassecrets。Eachtradewasacraft，andthosewhofolloweditwerecalledcraftsmen。Eventhecommoncarpenterwasahandicraftsman；andskilledartisanswere”cunningmen。”Butthehigherbranchesofworkweremysteries，thecommunicationofwhichtootherswascarefullyguardedbytheregulationsofthetradesguilds。Althoughtheearlypatentsarecalledspecifications，theyinrealityspecifynothing。Theyareforthemostpartbutamerehazeofwords，fromwhichverylittledefiniteinformationcanbegleanedastotheprocessespatented。ItmaybethatSturtevanthadnotyetreducedhisideatoanypracticablemethod，andthereforecouldnotdefinitelyexplainit。
Howeverthatmaybe，itiscertainthathisprocessfailedwhentriedonalargescale，andSturtevant’spatentwasaccordinglycancelledattheendofayear。
Theidea，however，hadbeenfairlyborn，andrepeatedpatentsweretakenoutwiththesameobjectfromtimetotime。Thus，immediatelyonSturtevant’sfailurebecomingknown，oneJohnRovenzon，whohadbeenmixedupwiththeother’sadventure，appliedforapatentformakingironbythesameprocess，whichwasgrantedhimin1613。His’TreatiseofMetallica’*
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ReprintedandpublishedattheGreatSealPatentOffice，1858。
showsthatRovenzonhadatrueconceptionofthemethodofmanufacture。Neverthelesshe，too，failedincarryingouttheinventioninpractice，andhispatentwasalsocancelled。Thoughthesefailureswereverydiscouraging，likeexperimentscontinuedtobemadeandpatentstakenout，——principallybyDutchmenandGermans，*
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Amongtheearlypatentees，besidesthenamesofSturtevantandRovenzon，wefindthoseofJordens，Francke，SirPhillibertVernatt，andotherforeignersoftheabovenations——
butnodecidedsuccessseemstohaveattendedtheireffortsuntiltheyear1620，whenLordDudleytookouthispatent”formeltingironore，makingbar-iron，&c。，withcoal，infurnaces，withbellows。”
ThispatentwastakenoutattheinstanceofhissonDudDudley，whosestorywegatherpartlyfromhistreatiseentitled’MetallumMartis，’andpartlyfromvariouspetitionspresentedbyhimtotheking，whicharepreservedintheStatePaperOffice，anditrunsasfollows：——
DudDudleywasbornin1599，thenaturalsonofEdwardLordDudleyofDudleyCastleinthecountyofWorcester。Hewasthefourthofelevenchildrenbythesamemother，whoisdescribedinthepedigreeofthefamilygivenintheHerald’svisitationofthecountyofStaffordintheyear1663，signedbyDudDudleyhimself，as”Elizabeth，daughterofWilliamTomlinsonofDudley，concubineofEdwardLordDudley。”
Dud’seldestbrotherisdescribedinthesamepedigreeasRobertDudley，Squire，ofNethertonHall；andashissistersmostlymarriedwell，severalofthemcountygentlemen，itisobviousthatthefamily，notwithstandingthatthechildrenwerebornoutofwedlock，heldagoodpositionintheirneighbourhood，andwereregardedwithrespect。LordDudley，thoughmarriedandhavinglegitimateheirsatthetime，seemstohaveattendedtotheup-bringingofhisnaturalchildren；educatingthemcarefully，andafterwardsemployingtheminconfidentialofficesconnectedwiththemanagementofhisextensiveproperty。Duddescribeshimselfastakinggreatdelight，whenayouth，inhisfather’siron-worksnearDudley，whereheobtainedconsiderableknowledgeofthevariousprocessesofthemanufacture。
ThetownofDudleywasalreadyacentreoftheironmanufacture，thoughchieflyofsmallwares，suchasnails，horse-shoes，keys，locks，andcommonagriculturaltools；anditwasestimatedthattherewereabout20，000smithsandworkersinironofvariouskindslivingwithinacircuitoftenmilesofDudleyCastle。But，asinthesoutherncounties，theproductionofironhadsufferedgreatdiminutionfromthewantoffuelinthedistrict，”thoughformerlyamightywoodlandcountry；andmanyimportantbranchesofthelocaltradewerebroughtalmosttoastand-still。Yettherewasanextraordinaryabundanceofcoaltobemetwithintheneighbourhood——coalinsomeplaceslyinginseamstenfeetthick——ironstonefourfeetthickimmediatelyunderthecoal，withlimestoneconvenientlyadjacenttoboth。Theconjunctionseemedalmostprovidential——”asif。”observesDud，”Godhaddecreedthetimewhenandhowthesesmithsshouldbesupplied，andthisislandalso，withiron，andmostespeciallythatthiscoleandironstoneshouldgivethefirstandjustoccasionfortheinventionofsmeltingironwithpit-cole；”though，aswehavealreadyseen，allattemptsheretoforemadewiththatobjecthadpracticallyfailed。
DudwasaspecialfavouriteoftheEarlhisfather，whoencouragedhisspeculationswithreferencetotheimprovementoftheironmanufacture，andgavehimaneducationcalculatedtoenablehimtoturnhisexcellentpracticalabilitiestoaccount。HewasstudyingatBaliolCollege，Oxford，intheyear1619，whentheEarlsentforhimtotakechargeofanironfurnaceandtwoforgesinthechaseofPensnetinWorcestershire。Hewasnosoonerinstalledmanageroftheworks，than，feelinghamperedbythewantofwoodforfuel，hisattentionwasdirectedtotheemploymentofpit-coalasasubstitute。
Healteredhisfurnaceaccordingly，soastoadaptittothenewprocess，andtheresultofthefirsttrialwassuchastoinducehimtopersevere。ItisnowherestatedinDudDudley’sTreatisewhatwastheprecisenatureofthemethodadoptedbyhim；butitismostprobablethat，inendeavouringtosubstitutecoalforwoodasfuel，hewouldsubjectthecoaltoaprocesssimilartothatofcharcoal-burning。TheresultwouldbewhatiscalledCoke；andasDudleyinformsusthathefolloweduphisfirstexperimentwithasecondblast，bymeansofwhichhewasenabledtoproducegoodmarketableiron，thepresumptionisthathissuccesswasalsoduetoanimprovementoftheblastwhichhecontrivedforthepurposeofkeepinguptheactivecombustionofthefuel。Thoughthequantityproducedbythenewprocesswascomparativelysmall——notmorethanthreetonsaweekfromeachfurnace——Dudleyanticipatedthatgreaterexperiencewouldenablehimtoincreasethequantity；andatalleventshehadsucceededinprovingthepracticabilityofsmeltingironwithfuelmadefrompit-coal，whichsomanybeforehimhadtriedinvain。
Immediatelyafterthesecondtrialhadbeenmadewithsuchgoodissue，DudwrotetohisfathertheEarl，theninLondon，informinghimwhathehaddone，anddesiringhimatoncetoobtainapatentfortheinventionfromKingJames。Thiswasreadilygranted，andthepatentNo。18，datedthe22ndFebruary，1620，wastakenoutinthenameofLordDudleyhimself。
DudproceededwiththemanufactureofironatPensnet，andalsoatCradleyinStaffordshire，whereheerectedanotherfurnace；andayearafterthepatentwasgrantedhewasenabledtosenduptotheTower，bytheKing’scommand，aconsiderablequantityofthenewironfortrial。Manyexperimentsweremadewithit：itsqualitieswerefairlytested，anditwaspronounced”goodmerchantableiron。”Dudadds，inhisTreatise，thathisbrother-in-law，RichardParkshouse，ofSedgeley，*
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