It becomes easy to see through the marvels of history when they themselves are transparent. This is the case with glass – a material so humble that its primary purpose has been perfected in making it nearly invisible.
Glass is everywhere around us. It is the window to our neighborhoods, the portal to distant lands, and even the reason some of us can see to start with. Who isn’t thankful for glass as the barrier between them and a 30,000-foot drop from cruising altitude?
All the Way Back
A material that is both natural and synthetic, glass itself has been around as long as the chemical elements silicon and oxygen. Naturally occurring Obsidian (volcanic glass) was traded and used for weapons and cutting tools since Fred Flintstone was chowing down on a rack of brontosaurus ribs.
Making its first appearance in the ancient civilization of Mesopotamia, the later portion of Egypt’s Bronze Age (some 2000 years later) saw the first rapid advancements in glassmaking. Among the glass items discovered from this period are ingots, vessels and the ubiquitous beads.
The 9th century BCE produced the first instance of colorless glass. The first manual on glassmaking dates to 650 BCE and was written on Cuneiform tablets (likely called “Glass from the Past,” though this has yet to be confirmed by archaeologists).
Grecian Glazers Urn Their Keep
The Hellenistic period of ancient Greece (323 BCE to 146 BCE) saw the next major advance as a more consistent technique for making vessels (which involved pouring viscous glass over a mould) was developed. The later portion of this period saw the rise of colorless glass.
Popular to this day, the art of glassblowing was discovered by the Romans along the Syro-Judean coast in the 1st Century CE.
Though of poor optical quality, the first cast glass windows began to appear on important Roman Buildings around the first century. As one of the empires closely guarded secrets, glass continued to be produced by the Romans until the fall of the empire in 476 CE.
Like Breaking Glass
The trade spread quickly after the fall of Rome and made its way throughout the whole of Europe and into the Middle East.
Until this point, all glass had been manufactured with soda ash. However, it was increasingly difficult for lands in Northern Europe to import soda ash. Around 1000 CE, a new technique was developed that used potash from burnt trees in place of the soda ash.
Lands along the Mediterranean and in the Middle East continued the use of soda ash (which any citizen of one of these places would tell you was “clearly the best.”).
Around this time, Germanic craftsmen developed a technique for making sheet glass that involved turning open a blown piece of glass and spinning it to flatten it out (like a pizza). The corners were then cut off to make the glass rectangle.
Venice All Said and Done
From the 11th to 13th century, this technique was perfected by Venetians and is likely the catalyzing event that led Venice to become the glassmaking capital of the world.
Stained glass, which was now being made by adding metallic elements to the glass product, had been around since the Roman Empire. With the world still being in its honeymoon phase with colorless glass, however, it was not until the 13th century that it became popular again with the emergence of the gothic and romanesque movements in art and architecture.
The demand for stained glass grew dramatically in this period. Much of the glass that was made in the this time period can be seen on buildings in Europe today.
A fear of the city’s fiery demise led Venetian officials to move the glass foundries to the nearby island of Murano in 1291. The quartz pebbles in the sand of Murano made it the ideal location to produce glass and the purity of the product became the top quality for the entire world.
Europe to the Plate (…Glass)
With a name almost as synonymous with glass as Philip Glass, George Ravenscroft would be responsible for the next major advancement in glassmaking. By adding lead oxide to molten glass, first in 1674, he saw a greatly improved appearance and longer time to form the glass.
Mr. Ravenscroft’s patent expired twenty years later and the production of boomed in England, becoming so profitable that the British government imposed a stern tax.
Excise Glass was born from this tax as glassmakers, in an effort to avoid taxation, created smaller, lower quality pieces often with hollow stems. The tax was repealed in 1845.
Having nearly been perfected by industrial process, glass got its big stage debut in 1851 with Joseph Paxton’s Crystal Palace, a building covered almost entirely with plate glass. James Hartley’s Cylinder Method for glassmaking, patented in 1832, made this grand scale construction possible.
Rather than blowing glass and spinning it like a pizza, the Cylinder Method pulled the glass from the fire then rolled, cooled and fed it through a series of rollers.
This not only gave glassmakers more control over the thickness of the final piece, but allowed much larger pieces of sheet glass to be produced (an immediate, although less publicized, effect was the sharp decline in the amount of injuries to glassmakers mistaking molten glass for pizza).
The mass production of glass began in 1887 with the Ashley firm in Castleford, England. The methods the firm employed allowed them to produce over 200 glass bottles an hour.
Licensing the Machine-Drawn Cylinder Method for glassmaking from United States inventors in 1910, Pilkington continued their dominance of the European glassmaking trade and were the main players in the development of Float Glass. Float Glass is a glass that has been poured unto a bed of molten tin and floats to the top when formed. Producing and marketing Float Glass became profitable on a full scale level in 1960 and, to this day, is used in many glassmaking applications.
History’s unsung hero, glass, has taken a long road to get where it is today. It hasn’t been pane-less either (that’s the last one, I swear). Understanding how much has gone into its development and perfection, we can continue to look through glass but it might be just a little harder not to see it.