bricks from the - Department of Architecture

8
Dr Stern then briefly describes his own experiments using two
sets of paste made up of clay and equal amounts of liquid. In one
case tap water was usedi in the other, an aqueous extract from straw
was used. Dr Stern is fully aware that 'clay of the kind used by
sculptors is not the same as the mud of the Nile, and English straw
may not be the same as that of Egypt, I but his results were nonetheless
interesting. Using a Rotovisco viscometer he measured the viscosity
of the two sampIes at different rates of shear. In all cases,
but particularly at low rates of shear, 'theviscosity of the paste
made with the straw extract was greaterby some 50 per cent than when
water alone was used'. As Dr Stern observes, this would result in 'a
more solid brick, less liable to be deformed during handling and
drying' .
This is an interesting comment on the use of straw by the Hebrew
slaves, and members interested in this period of the history of
brickmaking are urged to read Dr Stern's.article in full.
(TPS)
Notes and References
1. H.Stern, -'Bricks without Straw', Jewish Chronicle, 5945, 18 Nisan
5743/ 1 April 1983, 15.
2. The Haggadah (Heb. 'narration') is the service book used during
the Seder service/meal on the first night of Pesach/Passover in
the Jewish faith. Numerous modern editio~s, with English translation,
are easily available. Amongst other things it includes
an account of the slavery in Egypt. The Seder itself involves a
number of symbolic foods, including haroset, a (basically) nut
and apple paste intended to resemble.the material from which the
bricks were made. (Ed.)
3. The bricks, of course, were sun-dried, not burned. (Ed.)
ANGLESEY AND CLAY: Part 11
Bri-gadier Arthur
Trevor
1. Anglesey Kiln-Tiles. As a result of visiting old windmill and
watermill sites, fragments of various types
of kiln-tile have come to light: at present about twelve patterns
have been found. Two sources have been definitelyidentified from
impressed marks on fragments: (1) Sealy & Sons, Bridgwater, Somerset,
and (2) Ewloe Firebrick Co., Buckley, Flintshire (Clwyd). A third
impressed mark has been tentativel~ id~ntified asCatherall, also of
Buckley. The kilns (Welsh 'crasdy')were primarily for corn-drying,
but were possibly also used in the production of malt." All the
recently found tiles have square 'honey-combing' on the lower face,
and the norm appears to have been either five or nine perforations
per 'celI' in the 'honey-comb'. One very primitive specimen, from a