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The New Zealand Railways Magazine, Volume 15, Issue 1 (April 1, 1940)

A Flourishing New Zealand Industry — … The Ancient Art Of… — Brick and Pottery Making

page 49

A Flourishing New Zealand Industry
… The Ancient Art Of…

Brick and Pottery Making

The writer is indebted to Mr. M. Neighbours for the opportunity of being shown through the well-known Brick and Pipe Works of Messrs. Neighbours and Sons at Waimangaroa, eighteen miles from Westport. This kiln is the largest in the South Island, while experts consider that the clay in the vicinity is the finest of its kind in the world. The Neighbours family has been associated with brick-making for generations and the members of the firm are thoroughly conversant with every phase of the industry.

The history of brick-making takes us back to the days when primitive man discovered that by shaping moist earth into rough blocks, allowing them to dry, first in the shade and then in the sun, they became sufficiently hard to be used as bricks. Such sun-baked bricks would not be suitable in a land like ours, but in some countries, particularly Assyria, they proved to be so durable that bricks which were used over 6,000 years ago to build the city of Babylon, still remain. Strangely enough, cottages made of sun-baked bricks in certain parts of England are still inhabited, and are warm and comfortable in winter and cool and pleasant in summer. In some Eastern countries sun-baked bricks are used to-day, the same methods being employed as were adopted thousands of years previously. Some years ago an effort was made to revive the use of these bricks, but people prefer the properly baked ones as they are more durable and can resist far greater pressure.

Among the best accounts of early brick-making are those of the ancient Egyptians, who not only left written records but also valuable pictures of the men engaged in the making of bricks and pottery. The Nile mud which was used for this purpose shrinks greatly when dried, and unless the utmost care was taken the bricks would crack and fall to pieces. In order to obviate this the Egyptians mixed chopped straw and reeds with the clay, and were very careful to protect the freshly-made bricks from exposure to the strong sun or wind.

Although we refer to bricks as being made of “clay,” they are actually made from a complex mixture of clay, sand and other materials, for which the term “brick-earth” might be more suited. Pure clay does not contain sufficient fusible material to unite the particles when the bricks are heated. Sometimes brick-earth resembles garden soil, sometimes it is very sticky, and sometimes it is so hard that it would seem totally unsuitable for use. If limestone is present in the clay, it forms quick-lime when burned, and later the lime will slake and cause the bricks to fall to pieces. Chalk, however, is a valuable ingredient, because it is formed of minute particles, which, when heated, combine with the clay forming a fusible slag. This is particularly necessary for
Specimens in the pottery section.

Specimens in the pottery section.

the making of specially strong bricks. The colour of the bricks depends largely on the substances present in the clay. If there is much iron-oxide the bricks will be red, while under certain conditions they may be a blue-black colour.

In the Waimangaroa Brick and Pipe Works the machinery used and the various processes of manufacture are very interesting. The brick-making machine makes 6,000 bricks per day. The sandy papa used comes down into trucks and is shovelled straight into the pan. It is then crushed to powder by the rollers, and goes into the pug machine which fills the dice. The table turns for 30 seconds and then stops. This interesting machine has an automatic arm which pushes each brick out as soon as it has been pressed. The bricks are next put on a barrow and wheeled out to dry, which process usually takes a week, providing, of course, that the wind and sun are suitable. When dry, they are wheeled back to the kiln and burned at white heat for three days and three nights.

The clay for the manufacture of page 50 page 51
Pipes and fittings ready for transport.

Pipes and fittings ready for transport.

pipes comes from swampy pakihi land and resembles plasticine. It is carted to the yard by lorry and goes through the same process as the brick clay. From the pug mill it goes to the pipe machine. After the pipes are finished they are carted away from the machine and stacked on the floor to set. When set they are dressed, straightened on the rollers and put out to dry. The dressing consists of rounding all edges and putting on the “scratch” for cement connections. All Y junctions, bends, traps and various other fittings are made by hand. Pipes, unlike bricks, have to dry very slowly otherwise they crack. After drying the pipes are set in the kiln which is heated to 14,000 degrees Fah. At intervals during this process a shovelful of coarse salt is put into each fire-hole. The application of salt in this way puts a glaze on the pipes. It is interesting to note that it requires half a ton of salt and eight tons of coal for one burn.

Fire bricks are made from fire clay, nineteen acres of which is in the vicinity of the kiln. Fire clay is like a black slate and has to be subjected to great crushing before being reduced to powder. These bricks can withstand any heating conditions which would cause ordinary bricks to melt.

The most interesting part of the works was the pottery section, replete with the Potter's Wheel, the most ancient tool known to the potter. When Omar Khayyam stood in the potter's house making his observations he probably watched the craftsman manipulate the wheel, and it has changed but little in essentials through the passing centuries. The wheel is used for making deep, circular vessels, such as cups, jug, and bowls. It is a round piece of board set horizontally on top of a revolving spindle, the speed of which is controlled by the potter. He throws a lump of clay on to the wheel so that it sticks fast and revolves with the wheel. As the wheel spins he fashions the article, working from the base. His fingers, bent in a peculiar manner, touch the top of the article, and it rises into a vase. Another touch and the top rolls over into a lip.

The manipulating of the wheel demands deft fingers, skill and accuracy, and the many beautiful examples of the potter's art made on the wheel by Mr. S. Neighbours reveal these attributes in a high degree.