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Kokomo Opalescent Glass factory, located in Kokomo, Indiana. "Since 1888"

Kokomo Opalescent Glass factory. Vice President Dan Waber was interviewed.

"It has properties of a solid and properties of a liquid." Glass has 'viscous' molecules, that are irregularly spaced like a liquid but stay in place like a solid.

"It is strong, but can be transparent."

"Craftsmen in the Roman Empire discovered that adding manganese oxide produced clear glass."

"Adding lead to glass increases the refractive index. Crystal is glass containing at least 30% lead by weight."

"Kokomo was the leading supplier to Tiffany's at the turn of the century."

Kokomo currently makes "more than 22,000 different colors of glass".

"Cobalt blue is made using cobalt."

"Turquoise uses copper oxide."

"Yellowish green uses potassium bichromate."

"A deeper green uses a mixture of cobalt, copper oxide, and potassium bichromate."

"Amber uses sulfur or iron."

"Purple uses magnesium oxide."

"A brighter purple uses a mixture of magnesium oxide and cobalt."

"Red uses selenium or cadmium."

"A deeper red uses gold."

A "batch wagon filled with silica sand and soda ash".

Large bin of ingredients, "different metallic oxides to bring about the desired colors".

Gravity-pouring from a bin. "Adding ingredients like pot ash or potassium carbonate lower the temperature at which glass melts."

"The mixture is placed into a very hot oven, or pot furnace, where it forms a taffy-like consistency."

After being shovelled into the pot, it "melts for 12 to 14 hours".

Carefully removing the hot glass. "Hot glass is over 2000 degrees and very corrosive."

Carrying the ladles of hot glass over to the mixing table

"Colors are ladelled out onto mixing table, from as many different pots as there are colors to be included."

"The table man stirs it till it is mixed just right."

"Then the table man will drop it into the rollers."

"At that point the glass is about the viscosity of taffy."

A flat sheet of glass comes out of the rollers.

"Just takes a moment for the glow to come off it, and then the shove-in man can push it onto the belt into the annealing oven."

The annealing belt.

The cooled sheet of glass coming out of the annealing lehr.

Corning Glass Works in Corning, NY "has been producing glass for more than 150 years".

Corning's laborartory opened in 1908. "GE and Westinghouse were a little bit ahead of us, but not by much."

Corning's three major lab innovations were lightbulbs, TV picture tubes, and fiber optic cables.