Cylinder glass is one type of antique, mouth-blown window glass found in historical buildings dating back to the 1600s. It's also known as wavy glass for the bubbling, undulating imperfections found in the surface of the glass that distort images when you look through it.
Contrary to the urban legend that glass is a slow-moving liquid, it's actually a highly resilient elastic solid, which means that it is completely stable. So those ripples, warps, and bull's eye indentations you see in really old pieces of glass “were created when the glass was created,” Cima says.
For between $5 and $50, you can often walk away with some old glass. how much you'll spend just depends on the size and waviness of the glass. AGW makes some great wavy glass in several different grades of waviness to help you match the glass to the age of your project.
You'll most often find wavy windows in homes built before the 20th century, although glass doesn't get wavy overnight. Slowly, the glass in homes built in the early part of the 20th century will also begin to feature this unique distortion. It's somewhat of a myth that wavy windows are due to sheer age.
Most of this glass appears in homes from 1870 to the 1930's. You can still see the wavy nature of this glass as there still striations as the glass was lifted. After industrialization, the process and methods for making glass didn't change.
Properties of Wavy Glass
Glass produced between the 1700s and early 1900s have this antique “wavy glass” appearance. Another name for the old-looking glass is restoration window glass. The distortion and imperfections appear when looking at the glass from angles or looking straight through it.
According to AntiqueBottles.com, bubbles are rare in glass produced after 1920, so the presence of a bubble may help to date a bottle or window.
Sash Windows
Each of these type of antique windows usually has wood sashes, also known as muntins or lites, that framed the window and held the individual panes.
Drawn antique glass (also referred to as “GNA”) is also wavy glass with lines, but no “bubbles.” It is popular in cabinet doors and china cabinets.
A sash window or hung sash window is made of one or more movable panels, or "sashes". The individual sashes are traditionally paned windows, but can now contain an individual sheet (or sheets, in the case of double glazing) of glass.
While some people believe that the waviness is the result of the glass warping over time, the real reason for the wavy appearance has to do with the way glass was made at the time the home was built. There are two types of glass that were used in the 19th century: crown glass and cylinder glass.
FLEMISH. (Obscure visibility) Flemish glass has the look of hand blown glass without the seeds, bubbles, or the price tag. Light passes through while visibility is distorted – creating some privacy. This glass type offers an old world / slightly antique look.
Rolled glass is manufactured by pouring glass from the furnace into a series of rollers. It is then shaped to the desired thickness, annealed and cut to size. The two basic types of rolled glass are patterned and wired. Patterned glass is also called figured glass, obscure glass, and decorative glass.
If you look at glass in old windows, it can look distorted, apparently because the lower part of the pane is thicker than the upper part. Some people think that's because the glass, which behaves like a liquid at times, has sagged over time due to the effect of gravity. But scientists see through this myth.
Crown glass is a type of optical glass used in lenses and other optical components. It has relatively low refractive index (≈1.52) and low dispersion (with Abbe numbers around 60).
At the heart of the world's glass industry is the float process - invented by Sir Alastair Pilkington in 1952 - which manufactures clear, tinted and coated glass for buildings, and clear and tinted glass for vehicles.
The Italian name for glass with a regular pattern of air bubbles is "bullicante".
Definition of Florentine glass
: glass that is ornamented with embossed figures impressed (as by a roll) while the glass is still plastic.
Soda-lime glass production involves mixing together silica with 'soda' or sodium carbonate, and 'lime', or calcium oxide, before heating them together in a furnace at temperatures of around 1320 degrees Celsius. The molten mixture produced as a result is then worked into a shape and left to cool, producing solid glass.
To create the wavy glass look, squeeze out a little of the window coloring and spread around with a spoon to create that wavy texture. Though it's white while wet, it dries clear!
Factors like age, item type, size, colors, and condition affect the value of carnival glass. Pieces dating before 1940 are more valuable, as are complete sets of items and larger objects. Colors like ice green (which is sold for over $16,000) and marigold are rarer and highly prized.
Rain Glass, an addition to the Obscure Glass line from MI Windows and Doors, has a pattern that resembles water trickling down a smooth sheet of glass. Beyond the visual effect, the glass provides privacy and diffuses light, while resisting stains and fingerprints.
Fluted glass was popular in the 1920s throughout the Art Deco era, and it was frequently used in interior design with wall sconces and pendants.