Stained glass artist Henry Belcher and his New York based company produced some glorious work, as shown in this 1886 catalog offering a small taster of their output. The "mosaic" refers to the unique process which Belcher developed and for which he filed more than 20 patents. Instead of the traditional grouting approach, in which the individual pieces would be attached together, Belcher's method involved a kind of mold. He was the first to lay out the various pieces of glass in the design (hence the "mosaic" aspect), and then sandwich it between the two layers of asbestos (picking up the design with a gummed first piece and then closing it with a second) . Having previously made sure that there was a gap between each piece of the design, he'd then pour molten lead into the make-shift, mold, thus binding the various fragments of the design together.

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