Excavation Carlowan Du t sa y broch, Isl Lewif eo s by Christopher Tabraham with a report on the finds by Joanna Close-Brooks INTRODUCTION The broch of Dun Carloway has been in the guardianship of the State since 1887, during which time periodic works of masonry consolidation have been undertaken. One such occasion was the summer of 1971 when work was begun on the NE section of the broch wall. The comple- tio thif no s work necessitate disturbance dth archaeologicae th f eo l levels chambe withiE N e nth r and arrangements were made for the writer to undertake this over a 3-week period in June 1972. broce Th h (NG 190412B RN ) stands upo steena rockd pan y hillsid elittla e abov ovem a 0 r5 ese level (pi 7a). Fro wallheade mth t presena , t some 9- abov2m grounde eth , extensivee viewb n sca westere th f o nd seaboarha Lewisf do structure .Th bees eha n described elsewhere (RCAMS 1928, 68), Commission'thouge time th th f et o ha s visi Junn ti e 192 1greaa t quantit debrif yo s precluded productioe th accuratn a f no e survey opportunitn .A takes ywa n therefor re-surveo et groune yth d broce flooth f ho r durin perioe gth excavationf do . On plan (fig 1) the broch is roughly circular, measuring 14-3 m in diameter externally and 7-4 m in diameter internally, with walls varying in thickness from 2-9 m on the SE to 3-8 m on the chambee Th . Accesinterioe N rth NW (chambe o se t througs i rdooth w n , enterelo i r a hD) r d entrance jamth S fro f e bo mth e passage independens i , neighbous it f o t t r (chambeno d an ) C r formerl passagw lo a suggestes ya ey b linkeInventory. e t i th o dn dt i This latter feature seems merel havo yt e serve recesa s dchamber a chambese fo Th . rC r diametrically opposit entrance eth e (chambe describes a s Inventory,i e ) th B rn di t doubtbu s were expresse whao t s da t occupiee dth sectionE broce N th d f ho san wall recene N Th . t survey clearly shows that ther onls e eywa on chamber (chamber A) in this arc and that the second chamber suggested is no more than a small wall recess set immediately above the rock outcrop within the interior on the N. EXCAVATION wore confines Th flooe kwa th ro dt withi t extenno nd dchambedi int entrancd e oth an rA e passage (pi 7b). Excavation revealed an archaeological deposit, up to 0-7 m deep in the centre of the chamber, indicative of several periods of activity. The first was represented by a layer of ash lying directly upon the peat whilst above it was an assortment of ash deposits interspersed with layers of dark brown clay (fig 2). These are presumably a succession of hearths, though only one was recognisable as such. The natural subsoil was peat, which lay directly on the natural rock. The exterior wall of the chamber had been built directly on to the rock outcrop, and the relation- ship between wall, rock and peat was not known. The interior wall had also been founded on the rock but it is clear from the section that no overall removal of the overlying peat had been carried out prior to the broch's construction. TABRAHAM: EXCAVATIONS AT DUN CARLOWAY BROCH, ISLE OF LEWIS I 157 DUN CARLOWAY BROCH ROCK OUTCROP 10 Carlowayn Du FI G1 : pla f brocno h 158 I PROCEEDINGS OF THE SOCIETY, 1976-7 The earliest deposit was a layer of ash, sitting directly upon the peat and thickest towards the centrchambere th f eo .sig o Thern ns thaewa t thibeed s ha nhearth a , thoug flattiso htw h stones were found lying towards the bottom of the ash deposit, and several others had been mixed in with the fill. The ash itself was an orange-yellow colour. Presumably this and the other ash deposits were derived from peat, judging by the complete absence of charcoal flecks and the N CARLOWAYDU ; BROCH chambeA r BROCH BROCH WALL WALL BROWN EARTH ond STONES BROWN EARTH DARK BROWN ClAY FIG 2 Dun Carloway: section of chamber A and diagram showing layers in which artefacts were found existence of partially unburnt peats. This primary ash deposit had the appearance of being less intensely burn layerh t as tha e s nth abov . eit Upon this ash lay a band of brown earth up to 0-1 m thick in places and occupying up to two-third chambere chambee th thir th N f so f e droco d Th .rha k . slopinNW e gth gentlo t p yu Immediately above lay the only recognisable hearth within the chamber (fig 3). It was a complex structure comprising on the N a roughly flagged stone hearth containing ash, and on the S a shallow depression no more than 0-15 m in depth set into the underlying clay and having a drain, soakawayr o cornechamberE e th e f th ro n i ,ridg A . smalf eo l vertically placed stones separated the hearth fro pite mth . Botbeed ha hn t heartconstructepi d han d upo layena darf o r k brown TABRAHAM: EXCAVATION CARLN BROCHDU Y OT SWA A , ISL LEWIF EO I S15 9 clay containing small quantitie f ashe stonee hearto s th Th . f d beeo sh ha wern d l flaeal an t pressed into the underlying clay to hold them fast. The area covered by the overlying ash spread outward fro verticae mth l ridg t exceeno e aree d stonedth di a t occupies bu hearthstones e th y db . The pit adjoining the hearth was sub-rectangular in shape and had been formed out of the dark brow nfilles clay wa dnarro a t witI t . pi hwe eart th channe smald f o han d E l stonese ha l th n O . bee clae n provid th o y formet f o t edraida ou n int outee oth brochre walth f lono lA . g flat stone protruding fro outee mth r walpartialld an l y covere clae th y drainy e formed b sidth S f e o . dth XI BROCH WALL \ PREVIOUS EXCAVATION .^--' \ .'••""5^ \ \ FIG 3 Dun Carloway: chamber A, plan of hearth Immediately abov voia outletwale e s edth th wa l(fi n i g 3.1) 0-25 m squar penetratind ean e gth wal distanca l excesn ei metrea f o s . Thersimilaa s ewa r void (fig poina 3.2 t a ) littla t e over halfway alon e outegth rpossibla wald an l e cornee chambee thirth th f n di o r r diametrically oppose first e threl th Al . o det voids contained quantitie seconthouge h case th as f th f eo sdo n h i void this was associated with a hearth from a higher level. Overlyin hearth/pie gth deposia s t wa dar f to k brown clay mingled with eart containind han g patches of burning and stones. It occupied the whole of the chamber but was thickest at the entrance passage wher t attaineei ddepta fragmen A f 0-2 h. o 5m f rotaro t y subquera d -nan stantial quantity of coarse pottery, mainly small sherds, were recovered. The thickness of this laye claf beed ro centrchambee e yha n th th t reducef a eo m rmera m wher o d5 t e 2 voie d eth dha at first been filled with ash of a very bright orange-red colour, which in turn had been disturbed intrusioe byth anothef no t containinrpi g brown eartsprea h stonesd as h an e d Th .ove r mucf ho 160 | PROCEEDINGS OF THE SOCIETY, 1976-7 the central third of the chamber, but its breadth of 0-2 m at the point it met the outer wall of the chamber coincided exactly wit secone hth d void mentioned above. The last remaining deposits comprised two dark brown clay layers. Both had large flat stones pressed into their upper surface botd an sh were associated wit deposith has s upon them. They too must be regarded as hearths. A quantity of mollusc shell was found against the inner wall of the chamber, 0-7 m S of the entrance passage. Unfortunately its location immediately abov latese eth h deposi as ta laye n i tr comprising trace f anotheo s r clay laye moderd an r n trample reduces its archaeological significance; nevertheless a radiocarbon date was obtained for courtesy b t i f Geochroyo n Laboratories, Cambridge, Massachusetts. They prove havo dt n ea age of 650± 150 (GX 3428; using the best half-life of C-14). This implies that the sample can be dated to AD 1300 ±150 though this must be regarded as the maximum possible age since seashells characteristically give ages somewhat greater than 'true' due to apparent 'age' of seawater. On this basi Laboratore sth y favour trusa e 'age t lesno s' than 600-500 ±150 Ar yearo D P 140sB 0± 150. DISCUSSION The evidence obtained from the excavation shows that the chamber had been used con- tinuously over a period of time and had been abandoned only when access into it became almost impossible. At the outset of the excavation, for example, the headroom was only 0-87 m compared with 1-25 m from the surface of the first hearth to the underside of the door lintel.