Bricks have their own personality

Diagrams from Edward W. Hobbs, House Repairs, 1926.
Diagrams from Edward W. Hobbs, House Repairs, 1926.

Bricks surround us. They form the backdrop to our lives. The walls of our houses are mostly of red, or in some cases buff-coloured brick, and everywhere in this district are set off by the greenery of shrubs and trees. In the evening when the sun is low in the sky, walls, hedges and trees glow richly and soothe our spirit for the night’s rest.

On the night of the first election to what was then Morpeth Parish Council, our front garden wall fell down. Being a DIY enthusiast, I set about re-building it myself, as near as possible the same as the original.

Modern house-bricks are thinner than 19th Century ones, and hardly ever look right in that kind of situation. Engineering bricks are better. They are the same thickness as the old bricks, though a bit shorter, and have a good colour and texture, but I didn’t know about them at the time, so I went round the town seeking second-hand ones to replace those too broken to re-use.

What distinguishes old bricks from modern ones is personality. Our house dates from 1911 and is built of Bedlington bricks, the larger and better coloured facing bricks at the front, and Bedlington commons everywhere else.

There is a brick at the back, near the kitchen door, that a long-dead labourer at Bedlington colliery brick-works trod on while the clay was ‘green’. A hundred years later, we can still see the imprint of his hobs.

Most of these old bricks are unevenly burnt so that the same brick can be red in one place, dark blue in another where the heat was too strong, and almost white somewhere else. One that we have has a black pebble sticking out of it. It could equally be a fragment of another brick that got mixed in with the clay, but either way it gives it personality.

Colour also depends on the oxides of iron that occur naturally in the clay. The familiar red colour, so prominent in Bedlington bricks, comes from haematite, Fe3O4, but Pegswood bricks are often yellow, due to limonite, otherwise known as bog iron ore, Fe2O3∙H2O.

Fireclay, or seggar clay, occurs as the seat-earth beneath coal seams. It was the soil in which the giant ferns grew that eventually changed into coal. It has little or no pigment in it, and white or nearly white patches on housebricks are probably due to fireclay being mixed with the darker clays.

Brockett’s Glossary speculates that ‘seggar’ comes from the German ‘seiger’, a filter or strainer, because the clay turns to powder when exposed to the air, but I can find no reference to it being used for filtering, either now or in the past.

The same word, spelt and pronounced saggar, is found in the Staffordshire potteries, where it means a container of coarse ware to hold fine crockery during firing. On the basis that it was also used in the metal-working trades to describe a similar container made of cast iron, and that one early spelling of it was ‘seggard’, OED suggests that it might be a corruption of ‘safeguard’.

Fireclay is a valuable material. Mr George Brown, of Felton, a retired miner and, when I knew him, a long-serving parish councillor, once told me that the men got a higher rate for winning seggar clay than they did for coal.

Sir Joseph Cowen, the Chairman of the Tyne Improvement Commission who oversaw the building of the great piers at the mouth of the Tyne, made his wealth from the seggar clay found in the valley of the Blaydon Burn, inventing new uses for it, such as gas retorts and sanitary pipes, as well as the more conventional firebricks.

And, as we know from our own pages, the opencast coal mines on the Blagdon Estate and in the parishes of Stannington and Widdrington Station produce thousands of tons of fireclay every year, which nowadays is used mostly to make light-coloured bricks.

Old bricks often have names as well, stamped permanently in the frog, but naturally you can’t see it while the wall is standing. It only appears when the walls have been demolished and the bricks cleaned.

And that’s another thing; modern mortar is made with cement and is hard. It has no ‘give’ so that any considerable length of wall has to have vertical joints to allow for differential settling.

The old builders did not use cement, but lime. The specification for the mortar used in building the Borough Schools in Wellway in 1837, now Mr Richard Thompson’s accountancy practice, was three carts of river sand to one cart of lime.

Lime came as unslaked lumps from the lime-kiln, and these kilns were once a common sight all over the county. Deposits of coal and limestone, too small to be worked economically nowadays, provided raw material for kilns like those at Beadnell and Holy Island. Horse-drawn carts, or horse-drawn waggons on a waggonway, brought the lime. Coal, if there was none to hand, came to coastal sites in wooden colliers.

Old walls do fall down occasionally, but more often stay standing. Walls don’t stay up because the bricks are stuck together in a rigid panel, but because they’re vertical, or, like the leaning tower of Pisa, not so far out of true as to bring it down.

But if they have no vertical joints, how do they cope with settlement? My own intuitive and totally unscientific explanation is that, particularly after heavy rain or snow, moisture penetrates the bricks and lime so that the mortar refreshes and reconstitutes itself before settling down to decades more of quiet slumber. Like slow food, slow walls have a logic of their own.

I have a book, House Repairs by Edward Hobbs, published in 1926. Lump lime had to be kept in a dry place, and Mr Hobbs has a picture of an ‘extemporised cover’, like a tent with a platform for the lumps to stand on.

The same picture illustrates how to make lime putty, a material I have never heard of anywhere else: ‘Sink an old box into the ground, two-thirds fill it with lump lime, pour water over it, and leave it until it has slacked or turned into a creamy mass. This will take about a month. Cover the box with old wood, sacking etc., to exclude dust and dirt.’

It also shows you how to make mortar. Once again, time was an ingredient.

‘Mix equal parts of unslacked lime and clean sand on a board, sprinkle with water from time to time, to keep the whole moist, and turn it over with a fork about once a day for a week. Then leave it to temper for another week.’

A month! A week and then another week! What builder nowadays would want to wait that long for his putty or his brick-laying mortar?