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"A Fresco is a kind of painting performed on fresh plaster, or on a wall covered with mortar not quite dry, and with water colors. The plaster is only to be laid on as the painting proceeds, no more being done at once than the painter can dispatch in a day. The colors, being prepared with water, and applied over plaster quite fresh, become incorporated with the plaster, and retain their beauty for a great length of time."—(Charles Leonard-Stuart, 1911)

Fresco Ceiling

"A Fresco is a kind of painting performed on fresh plaster, or on a wall covered with mortar not quite…