Monklands Memories - Airdrie & Coatbridge areas

Brick Making
(ordinary bricks that is)
with thanks to US Army Corps of Engineers

A brick is made from a ceramic structural material that, in modern times, is made by pressing clay into blocks and firing them to the requisite hardness in a kiln.

Bricks in their most primitive form were not fired but were hardened by being dried in the sun. Sun-dried bricks were utilized for many centuries and are used even today in regions with the proper climate.
Examples from approximately 5,000 years ago have been discovered in the Tigris-Euphrates basin, and the ancient races occupying this region may have been the first users of brick.

In Babylonia there was a lack of both timber and stone, and the thick clay deposited by the overflowing rivers was the only material adaptable to building. The Persians and the Assyrians used sun-dried blocks of clay for walls of great thickness, facing them with a protective coating of fired bricks. The Egyptians and the Greeks used bricks only to a limited extent, as they had access to plentiful supplies of stone and marble. The Romans manufactured fired bricks in enormous quantities and gave them an important role as a basic structural material in buildings throughout the Roman Empire.

Bricks played an important part in early Christian architecture until the decline of the empire. Whereas the Romans had usually concealed their brickwork beneath a decorative facing of stone or marble, the Byzantines devised a technique for exposing the bricks and giving them a full decorative expression. This technique influenced the Romanesque style and brought especially good results in Lombardy and in Germany, where bricks came to be arranged in immensely varied patterns.

Since the Middle Ages, brickwork has been in constant use everywhere, adapting itself to every sort of construction and to every change of architectural style. At the beginning of the 19th cent. mechanical brick-making processes began to be patented and by the latter half of the century had almost entirely replaced the ancient hand-fashioning methods.

Good bricks are resistant to atmospheric action and high temperatures and are more durable than stone. Where heat resistance is especially important, fire bricks are used; these are made of special refractory clays called fire clays and are fired at very high temperatures.

It is important for industrial archaeologists to have knowledge about the architecture and layout of buildings so that they can gain key insights about the purposes for which the buildings were used.  Knowing how the equipment within the buildings was utilized plays a very important role in our understanding the evolution of technology.  Archaeologists are very interested in looking at the changes in technology to see how they may have affected the success or failure of businesses.

In the late nineteenth century, most brick works had similar components.  First, soak pits were used to prepare and mix clay.  Clay was mixed with water and soaked overnight for softening.  By doing that the clay became more pliable so that it could be shaped into bricks using wooden forms.  Once technology began to take over, molding the bricks into the proper shapes became easier by using a soft-mud brick machine.  The machine automatically shaped the pieces of clay into the form of bricks.  A talented brick maker could produce about 4,000 bricks per day by hand.  By the 1890�s, some brick machines could even produce up to 5,000 bricks per hour.

The next step in the process was drying the bricks so they would be hard and durable.  The brick-makers would put the soft bricks into a steam-heated drying room.  The drying room was generally the largest area of a brick works facility because they had to accommodate such a large amount of bricks at a time.  Towards the end of the existence of the brick works, the company bought a drying tunnel,  which allowed the bricks to move through the drying room by a conveyor belt with steam heat blown on them.  By using a drying tunnel as opposed to a drying room, a much higher quantity of bricks could be dried and finished at a time, allowing higher sales and saved labour.  Before the technology of drying rooms and tunnels, brick-makers had to lay bricks outside to dry naturally in the sun (and hope that it didn�t rain). 

The last part of the brick-making process was to fire the clay in kilns, which produced a very high degree of heat to cook the clay before it went through a final drying process.  By cooking the clay, all of the finer elements were fused with one another to create a stronger, more durable, solid mass.  Once the clay went through all of those processes, it had completed its metamorphosis to brick. 

There is evidence that by 1898, the Harmony Brick Works had eight kilns altogether.  There were five large kilns and three smaller ones. The kilns were fuelled by natural gas and coal.  By the end of the 1890�s, natural gas supplies were diminishing, so workers were forced to resort to using a combination of coke and slack coal to heat the kilns.  At the Harmony Brick Works, it was possible to fire many bricks at one time.  According to an 1898 article about the Harmony Brick Works, the five larger kilns could hold 375,000 bricks apiece.  The three smaller kilns had a holding capacity of 150,000 bricks.  The trade-off for having a high quality of bricks that could be fired at once, was that it took two weeks for each kiln, large or small, to complete the job.  They were slow-burned and cooked evenly and thoroughly.  The bricks had to be laid out in such a manner that all sides got fired.  Sometimes it was necessary to lean them against the wall on their corners to get heated thoroughly.  The Harmony kilns were of the periodic up-draft, open-top variety.  That means that the kilns had an open top and the bricks were stacked in the kilns so that they had spaces for air circulation.  The bricks were burned so that the fire and smoke rose upward to escape from the tops of the kilns.  This type of kiln is very efficient for burning many bricks at a time.

The property also included buildings such as a boiler and an engine house to convert energy to heat for firing and drying, storage sheds for quantities of unused brick, a grinding house for grinding the finer elements of the clay, and an office for accounting purposes.  The layout and geographical location of the company�s structures were quite practical.  It made sense for brick factories to be located near a water source, clay deposits, and natural heating resources such as coal or natural gas so that there was increased availability of resources at a cheaper cost.  Another essential architectural component of brick facilities was the serviceability of building related structures within close proximity of one another.  For example, the clay processing facility, the moulding and drying areas, and the kilns were built in a cluster for the purpose of minimizing the time it would have taken to transport all of the bricks from one area to another.  In turn, it saved on labour costs.