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XI. On the Structure and Arrangement of the Tesserce in a 

 Roman pavement discovered at Cirencester in August 1849. By 

 James Buckman, F.L.S., F.G.S* 



THE object of this paper is to point out the nature of the 

 materials of which the party-coloured floors so beautifully- 

 wrought in ancient Roman dwellings are composed, ' as also to 

 offer some remarks upon their principles of arrangement. 



The tesserae of Roman pavements may be said to be formed 

 out of two classes of materials, the first of which, consisting of 

 portions of various coloured rocks, may be termed natural ; the 

 second, of stained or coloured terra cottas and glass, being arti- 

 ficial. 



The natural tesserge furnish but few colours, and those of a 

 sober cast, hence these will be found forming shadings to figures 

 entering largely into the composition of borders, or filling up the 

 groundworks of the designs. They consist of portions of natural 

 rocks from various localities, those belonging to the district where 

 the pavement is found, as far as I have observed, always contri- 

 buting their share. 



The Cirencester pavement presented the following : — 



Colours. Rocks. 



1. White, composed of Hard fine-grained Oolite. 



2. Light yellow Pebbles of the Wiltshire Drift, and Oolite. 



3. Gray The same as No. 1, altered by heat. 



4. Slate colour or black ... Limestone bands of the Lower Lias. 



No. 1 occurs as a bed of compact fine-grained stone of about 

 2 feet thick in nearly all the freestone quarries of this district, 

 where it is distinguished under the name of the Limestone bed ; 

 its geological position is about the middle of the freestone rocks 

 of the Great Oolite ; it is well exposed at Trewsbury quarry, at 

 the Acrnan Street Station, and at the smaller Sapperton tunnel, 

 and was no doubt obtained by the Romans from the quarries 

 once worked by them in the vicinity of the Querns. 



2. The tesserse, of a yellowish or nankeen hue, appear to 

 have been made of portions of the pebble-drift with which parts 

 of the neighbourhood of Cirencester is so thickly strewn. Stray 

 pebbles of this may be found in almost every field to the south 

 of the town, whilst at Somerford Kaynes, and other places, it en- 

 ters largely into the composition of the gravel beds which are 

 there worked. It is probable that this drift is the debris of that 

 tertiary rock known in Wiltshire as Sarsen stone, of which the 

 huge stones of Abury Camp constitute the more enduring mo- 

 nument. 



3. This, though differing so much in colour from No. 1, yet 



* Read to the Cotswold Club, Jan. 22, 1850. 



