book of hours

   A book for private devotions containing prayers for different hours of the day. Each book of hours is a a collection of texts for each liturgical hour of the day, along with other texts such as calendars, prayers, psalms and masses for holy days. Often these books were richly illustrated with illuminations. A classic book of hours is Les Tres Riches Heures, one of the great art treasures of France, the greatest achievement of the art of manuscript illumination. It was painted by Paul, Hermann and Jean Limbourg (brothers, Flemish, each c. 1380-1416), 1412-1416, for the very wealthy Duke of Berry, a brother to a king and other dukes. The Limbourgs used a variety of colors obtained from minerals, plants or chemicals, mixed with either gum arabic or gum acacia to provide a binder for the paint. Among the more unusual colors they used were vert de flambe, a green obtained from crushed flowers mixed with massicot, and azur d'outreme, an ultramarine made from crushed Middle Eastern lapis-lazuli, used to paint the intense blues, and extremely expensive. The fine detail which was characteristic of the Limbourgs demanded extremely fine brushes and, almost certainly, magnifying lenses.