THE ENIGMATICWATER-MILL by tsradf<,rrdB. Blaine Marc Bloch,writing ncarly forty yearsago, brilliantly cornprcsscd into a brief articleenouglt documentation to suggestthat the water-powcrcdgrain-mill bccarnc a basicleature of Medievallile; his findings pointcd,ntorcovcr, to tlte applicationot'hydraulic cncrgy to variousother industrialprocesses Sluring the MidtllcAges.l Subsequentto Bloch'spioneering efforts, Bertrand Gille2 and R. J. Forbes3hou. thrown wide nets,adding extcnsivcly to our invcntoryof mcdicvalwater-powcred devices, while detailcdregional studies such as those of A. M. Bautier,4Germain Sicard,5 and E. M. Carus-Wilson6 havcrevcalcd clear indications of local industrialdcvclopmcnt related to the ernploymcntof hydraulic mcchanisrns.Lynn Whitc,moreover, includes thc explorationand uscsof water-puwerarnong thc technologicalfactors wlrich hc recognizesas critrcalin the forcesof attitudinal,/social,u and economic9changc during the MiddleAges. For all its known incidences,howevcr, and for all that we suspectconcerning its importance,therc is an immenseanonymity rcgardingthe medievalwater-mill. Unccrtainticssurround its genesis, diffusion,and anatomies,and thcsein turn encumberthe searchfor new data and for furthcr insightsinto its significancc.To illustratcthe nature and exlent of the problem and to give somc usefuldirection to thc currcnt enthrrsiasmfor the subjcct,thc presentpaper probesthree specific dilemmasconcerning the historyof the water-mill.l0 l. A Problem of Origins The first known attempt in the West to harnessthe energyof running water for practicalindustrial purposesreflects in the appearanceof the water-poweredgrain-mill in the late first century B.C. This is not to deny the contemporaryexistence of relateddevices. The norfu, for example,a vertical wheel fitted with paddlesand buckets,drew water for irrigationfrom the current which turned it.1l And Greco-Romanengineers conceived a variety of hydraulicautomata in which runningwater turned wheels;the sole objective,however, was the turning itself or the noise thus produced,l2 of little practicalvalue except as temple tricks. In none of thesewas there the transmissionand use of the power available. With the grain-mill, however, the energy was indeed transmitted from the wheel and utilized by a grinder. The earliestcertain Western evidence of this comesfrom the writingsof Antipater of Thessalonica,Strabo, and Vitruvius,as well as from somecarefully studied archaeolosicalremains. 164 B. B. Blaine Alr epigrantattributed to Antipalcrannounccs the cmanciputi()nof'nraitlservants frt-rnr the drudgcry of hand-rnilling: Ccascliont grinding.yc womcll who tclil:rt thc rnill; slecplate, cven if'thc crowingcocks anncluncc the dawrr. For Dernetcrlr;.rs ordercd thc Nyrnplrsto to performthe work of your hands,and thcy, lcupingdown on top of tirc whcel,turn its axlc which,with its revolvingspokcs, turns tlte lreavyconcavc Nisyriantnill-stoncs. We tasteagain thc jclysof-tlrc prirnitivclil'c. learning lo fcaston the pr<tductsof Dcrneterwitlrout labour.t' Thcr,--can be no doubt tlrat this rcf'ersto u watcr-nrill.And it wasprobably Grcck, dating front thc lastdccude tlf the firstcentrlry B.C.l4 Tlrc typc ol the rnill.howcver, is not at all ccrtain. lt rnav havcbt'cn a futrizttntalau7l, consisting of a lrorizontllwrtcr-wheL.l witlr u vcrlicalaxlc attachedal tlrc t<rpto the uppcr of two grindstoncs.l5OI. it ma1,hlve bccnu t,ertit'alnll/, consistingol a vcrticalwatcr-wheel witlr its horizorrtrlaxlc gcarcdto a vcrticaluxle, whiclr in turn contrnurricatcs thc drivc to thc stoncs Suchr wheclcln rcceivethc wutcr as it ll<twsbelow (untlcrshot) or as it is l'cdfiorn abtlvc(ovcrslrot).16 Antipater's nynrphs arc, to bc surc,leaping "clown," and thc "sp<lkcs" may rcfcr to the cogsof a gcarrathcr than to tlrc spokcsof l wlrccl,lhus indicutingI vertical ovcrsh<ttmill." On the other lrand,thc rel'ercncenray bc to watcr rushingdown I chulc irrto tlre' sideof a horizontalwhcel lnd to radiatingiron tlangcs(a dovctail)cornprrsing the lttachrncntof' thc top ol the shaft to thc uppcr nrillstonr'.18Thc cvitlencc,howr.ver, is inconclusivc:Antipatcr's poctry praisesa watcr-nrillbut iails to clcscribcit.l9 Thc sanrcsort ol uncertainticssurrountl llte h.t,draletuwhrch Strabr) says was forrrrdat Cabirl, Pt>ntus,on thc LycosRivcr nearlhe palaceof Mithritlatcswhen the placetcll to Pompo,in (r5 tl.C.20 If thc cleviccwus built with the palaccin 120 B.('., it woulclantedttc Antipater's rnill by ,n.uy y..rr.2l Thcre'is,howevcr, no evidcnceol'this; thc earlicstdatc'that cart rcasonably be assignedis 65 B.C., whcnthe rcportedevent ()ccurrcd, althouglr the salestestimatc is ca.7 B.C.,at whichtimc Strabo was travclingand writing the Gu1raphiu.'- lt is impossihlc,nrorcovcr, to fashionfrt>m tlrc rcporl any kind of positivedcscriptiorr.zr Vitruvius,a Rornancnginccr writing no laterthan l4 8.C..is lhc first to providctcchnical dctail. llc clrel'ullydescribcs a verticalunclcr-shot nrill, includingthc-csscntial gearing.24 Gearirrg harl bcen r) known in the HcllenistrcWorld sincc the third ccntury'8.['., brrtVitruvius's mill repre.scrrtsits first inclustrialuse antl rrtarksa clccisivcstep in the devclopnrcntof'powc-r nrcchanisn,s.26 ('oncurrcntwith thescevents in tlte MeditcrraneanWorld wls thc probableappcarlncc in Scarrdinavia of the horizontalgrain-mill. Excavations at Bolle,Jutiand. revcal traccs of two dam sitesdalirrg frorn tltc beginningof thc Christianera. lncludedin tlqescis clcarcvidence ol the danrs.rcscrv()rrs and races. Carefulanalysis of silt depositsindicates, moreover, not only rnillsbut alsothat thc1, werc of the horizontaltype."' The earlysimultaneous appearancc of the verticalwater-rnill in Romansourccs, lirmly establislred, and of the horizontalmill in northernEurope, strongly indicated, corncidcs with the earliest reportof water-powerat work in China. JosephNeedhanr shows conclusivcly that hydrauliccncrgy wasin use thereby 20 A.D. to driverice-hulling trip-hamrners and by 3l A.D. to work rnetallurgical bellows. Althoughillustrations are lackinguntil the early lourteenthcentury, his analysisof thc total evidenceindicates that the horizontalwater-wheel was used as a motive forcc from the t'irst The EnigrnaticWater-Mill 165 ccnturvonward, as with thc bellows,and that the verticalwatcr-wheel, though lcss common in China, datesfrom a comparablyearly pcriod, espL'cially in associationwitlr trip-hammermechanisms, whiclt are lnore intclligiblein that cotrtext.rd Ncedham,moreovcr. provides evidcncc from Chinesesources ol-yct anothcrhydraulic device, a watcr-poweredspoon tilt-hammer (iill-and-spill mechanism), again not ill,rstratecluntil thc fourteenthccntury but mcntionedin tlre literatureby the mid-twelfthccntury and probablyof greatcrantiquity.29 Onc wonciers,in lact, how far back into Chinesehistory tltis gocsand tltc cxtent to which it may havccharacterized thosc first trip-hammers,or cvcn the bellows. Clearly,thc point ol originof the conccptof watcr-drivenmachincry rcmains problematical. Vastly^ separatcareas and threediffercnt kintls of mechanistnare involved. Argunrentsciting either Chinaru or thc Grcco-RomanWorld3 I abound,but they remaininconclusive. Engaging but equallyundemonstrable at prcsentis thc suggestionrrthat somemiddle ground may be criticalhere; that is, sornemobile Eurasianpcoplc hit upon the conccptof water-powcredmachincry and was the instrumentof its dil'fusion.various adaptations being effccted wltereverthc idea was reccivccl..A final possibility, arguablclrom thc prescntstatc of the cvidcncc,is that therewcre severalvirtually simultaneous invenlions: the vcrticalmill-an effcctivcconrbining of rccentlydcvcloped rotary grindstoncs,gears and the noria in thc easternMcditerrancan, the horizontalmill in northernEurope and in China, and the fill-and-spilldcvice in E,astAsia. 2. A Problem of Predominance Evidenccof tllc water-powcredgrain-mill in tlic Westaccumulatcs from the time of Vitruviusonward. Sincc,howevcr, so little ol'the testimonyis descriptive,consisting rather of casualreferenccs or cntries in property inventoriesand r.ltherlegal documents,Jrit is not clear which of the basictypes of grain-millwas preferrcdand/or most extensivelyused. The total relativelyunambiguous evidencc of the verticalundershot, vertical overshot, and horizontalmill for over a milleniumcan be organized into a lew brief paragraphs. With respectto the undershotarrangement, our carliestdescription is that of Vitruvius,discussed abovc. Next, relatingto the tragiccataclysm of 79 A.D., Italianarchaeologists have reconstructcd a water-wheelfrom volcanicash impressionsfound at Pompeii. Piecesof the cast and the reconstruction are in thc MuseoNazionale in Naples. The wheel,having eighteen paddles set betweenparallel rims, is of thc vertical typ..34 Our first picturc of any water-millis includedas part of an early fifth- ccntury mosaicin the Great Palaccof Byzantium. None of the internal mechanismis shown: merely the wheeland thc mill-house;but the wheelis standingvertically over the water.r) No vertical undershotmill appearsagain for nearly 800 years;a late twelfth-centurymanuscript of L'lmage du Morule,by Gautier of Metz, containsthe externalview of a mill-housewith an undershotwheel,36 as doesa thirteenth-centuryminiature in the Vieilrentier.ST Our first indisputableillustration of the gearing^associatedwith an undershotmill appearsin a South Germanmanuscript dating from ca. l205.iu A late thirteenth-orearly fourteenth-centurySpanish reliquary provides internal detail of an undershotmill, includingthe water-wheel,axles,