This section is from the book "Chromatography; Or, A Treatise On Colours And Pigments, And Of Their Powers In Painting", by George Field. Also available from Amazon: Chromatography, or A Treatise on Colours and Pigments, and of Their Powers in Painting.
Burnt Umber is the fossil pigment called Umber, burnt, by which it becomes of a deeper and more russet hue. It contains manganese and iron, and is very drying in oil, in which it is employed as a dryer. It may be substituted for Vandyke brown, is a perfectly durable and eligible pigment in water, oil, or fresco, and may be produced artificially. The old Italians called it falsalo.