Londinium : architecture and the crafts / by W. R. Lethaby.

  • William Lethaby
Date:
[1923]
Catalogue details

Licence: In copyright

Credit: Londinium : architecture and the crafts / by W. R. Lethaby. Source: Wellcome Collection.

    17/256 (page 13)
    of, or in conjunction with, sand.” In Rochester Museum a dishful of the crushed tile is shown which was taken from a heap found ready for use at the Roman villa at Darenth. I may say here that I have found mortar prepared in this way wonderfully tenacious, and suitable for special purposes like stopping holes in ancient walls. A strong cement made of finely powdered tiles, lime and oil was used by Byzantine and mediaeval builders and probably by the Romans also. Villars de Honnecourt (thir¬ teenth century) gives a recipe : “ Take lime and pounded pagan tile in equal quantities until its colour predominates ; moisten this with oil and with it you can make a tank hold water.” The use of crushed pottery in cement goes back to Minoan days in Crete. In London a long, thick wall of concrete formed between timbering was recently found between Knightrider and Friday Streets ; it showed prints of half-round upright posts and horizontal planking; it bent in its course and may have been the boundary of a stream. On the site of the old Post Office a Roman rubbish pit was found, about 50 ft. by 35 ft. in size. “ In late Roman times the whole pit had been covered with concrete about a foot thick and a building had been erected on the spot ” (Archceol. lxvi.). At Newgate the Roman structure was erected on a “ raft ” of rubble in clay finished with a layer of concrete. Rubble in clay formed the foundation of the City Wall. Many walls, described as of chalk, rubble or rag-masonry, have been found in London—one instance at the Bank has been quoted above. Chalk and flints were the most accessible material after local gravel, clay and wood. Mr, F. W. Troup