Laeken: City of Glass
The first part of Dr. Stephen Becker's fascinating
two-parter. This explores the history of the glasshouse from Roman
Dr. Stephen Becker, 21 Westfield Grove, St. Johns, Wakefield, Yorks
Chamaerops No. 7, published online 23-10-2002
on this article:
Click here to read them or to add your own.
Left: The Palm Tree Pavilion.
Right: Room to grow - Inside the wintergarden.
Gardeners since time immemorial have sought to manipulate
the conditions of cultivation in order to accelerate plant growth,
extend the growing period and improve the harvest.
Utilising the transparent rock, mica, the Romans
developed greenhouses in order to provide the conditions necessary
for the cultivation of plants brought from Egypt and Asia. There
is evidence that some of these structures were heated.
The earliest traders and then the explorers brought
back seeds, exotic fruits and flowers that had never been seen in
northern Europe. The new flora aroused scientific and private interest.
The knowledge rapidly accrued that they required special climatic
conditions in order to flourish and that overwintering of plants
required that they be protected from the cold and frost. The great
scientific institutions of the time studied these plants in order
to discover their utility. It became prestigious for the nobility
and the wealthy to own and display foreign and exotic items in their
private collections. The solution to the preservation of exotics'
The smaller specimens might be placed in pots, which
were taken indoors for winter. Large specimens such as citrus trees
were planted in enormous tubs and kept outdoors during summer. They
were overwintered in special buildings such as the Orangery. Specimens
planted in the ground had wooden sheds erected around them in situ
before the first frosts arrived.
Permanent houses were also built from brick and
stone for all season cultivation of pineapples and citrus trees.
The principal of construction was a stout north facing wall which
would keep off the coldest wind but which would also act as heat
exchanger, absorbing the sun's rays on warm days and releasing heat
at night. The size of windows was a problem as was the maintenance
of a heated environment.
Orangeries were first heated by open braziers and
then by means of fires using flues. Another solution to the problem
was to construct the buildings with vaulted underground chambers
from which hot air circulated. Eventually there came greenhouses
into which steam was directly released, followed in 1830 by the
invention of the piped hot water central heating system.
Prior to 1688, man-made glass was made in blocks
and sawn into layers. It contained air bubbles, which unfortunately
acted as magnifying lenses and had the effect of scorching the plants
behind. By 1688 glass production had improved and it was possible
to make sheets by pouring it onto metal tables without the introduction
of air bubbles. This enabled the construction of large windows for
the admission of light into the greenhouse or orangery. The advent
of industrial techniques in the nineteenth century saw a veritable
explosion in the use of high-quality glass and combined with the
revolutionary developments in iron manufacture, a new era came about.
The Age Of Iron
Iron which had been known since ancient times was
a difficult material. It corroded easily and was unavailable in
large quantities but by the end of the eighteenth century it was
being used in limited quantities as a building material. But in
1783, Cort 'reverbatory' process improved pig iron by 'puddling'
it and obtained a non-rusting and forgeable material. Bessemer's
process allowing the manufacture of massive quantities of steel
set the stage for a revolution in building techniques. Masonry was
replaced. Steel and glass became the most important construction
materials until the end of the nineteenth century.
The Hot House
The traditional greenhouses, stove houses and orangeries
had achieved architectural elegance but had certain limitation in
terms of size, space and light. It was also unfortunate that high
humidity and heat was merciless in degrading wood and masonry, and
took its toll. Many of the most beautiful orangeries and greenhouses
Just never survived. Even the rich could not afford their colossal
upkeep after the initial capital outlay. They had, however, demonstrated
the practicability of enabling plants from tropical, sub-tropical
and warm-temperate climates to survive the harsh north European
It was not until the nineteenth century that technological
sophistication enabled the construction of large steel and glass
structures. Steel, glass and central heating allowed new types of
buildings and a new aesthetic. Masonry was replaced in greenhouse
construction. Exotic specimens requiring enormous space and with
exacting light and heat requirements could now be housed in large
curvilinear domes which were to assume graceful and fantastic forms,
culminating in Art Deco.
Leopold II succeeded his father to the Belgian throne
in 1865. He had a clear understanding of Belgium's position in Europe
and the world and spent his entire energy in remedying the situation.
Of all the major civil works programmes he initiated, the development
of the Royal Estate at Laeken, was probably the project closest
to the King's heart - part of his vision of making Belgium rich,
respected and culturally advanced.
At the time of his accession, Laeken consisted of
some 80 hectares. Two years later, Leopold made a decision to create
a Public Park but it was not until 1876 that the plan was begun.
Over the next thirty years, by various means, fair and foul, the
Estate was systematically extended. Residential districts were purchased,
private estates acquired or expropriated, and local council opposition
quelled. So, by the time of his death in 1910, the Royal Estate
occupied an enclave within a larger public park of 186 hectares.
Broad avenues linked the park with Brussels and
the rest of the Belgian road network, and provided a protective
cordon around the Estate enabling it to remain untouched as the
rest of the city developed. The whole area was landscaped, two large
lakes excavated and a reservoir dug to service the water requirements
for his ambitious Greenhouses.
The Royal Greenhouses
In 1834, the first greenhouse of iron and glass
was constructed in Paris for the Natural History Museum at Fleury.
In the same year the Royal Botanic Gardens in Edinburgh was built.
The glasshouse at Chatsworth of 1836 was with its greatly advanced
heating and ventilation system to influence all subsequent greenhouse
construction. The Palm House at Kew was built between 1844 and 1848.
It was to inspire all that followed. In 1851, the great Crystal
Palace popularised the use of iron and glass all over the world.
Further advances in the iron and glass building field came with
the opening of the Palmengarten in Frankfurt in 1870. This was the
first large greenhouse built with no supporting members thereby
allowing an unimpeded interior view.
The decision to build a winter garden at Laeken
was taken in 1868 after Leopold's visit to Frankfurt, and having
learned of the intention to build a Palmengarten there.
City Of Glass
The King enlisted the services of the architect,
Alphonse Balat. By 1874, the first sketches had been drafted and
in July, the construction of the frame of the Winter Garden was
started, and completed in 1875. In 1876, the dome was covered with
glass. The heating system was installed and became operational by
March 1879. In the bitter winter that followed, temperatures fell
to 32°C, but the temperature within remained satisfactory thus
allowing the structure to be planted the following year.
Whilst the colossal Winter Garden was built, the
Orangery was enlarged, and the Camelia House, Dining Room Greenhouse
and Theatre Greenhouse were constructed, as well as the connecting
In 1880, the Palm Tree Pavilion was built, two large
lakes excavated and a reservoir for the greenhouses. In addition,
a water catchment station was added in 1885 as well as two large
and two small cultivation greenhouses. One of the large ones is
now the Azalea House.
Leopold became head of the Congo Free State in 1885,
and in order to houseplants from Africa had the large Congo Greenhouse
constructed the following year at the same time as the Embarcadero.
An electricity station allowing electric lighting followed. During
1890 the Royal Palace underwent extensive renovation following a
fire, and undeterred, work commenced on the Palm Tree Plateau, comprising
the Pavilion, the Palm House and the Debarcadere. The Iron Church,
also of iron and glass, was added later. The City of Glass was completed
Well, that's the history lesson over. In the next
edition we take a trip to Laeken and spend several happy pages exploring
The City of Glass - a dazzling and unforgettable experience. Don't
(No comments yet. Be the first to add a comment to