WOODBLOCK PRINTING
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grain blocks. End-grain blocks are suitable for fine close cutting and are also well suited to bear up under the pressure of printing. Large number of prints can be produced from them. End-grain blocks were widely used in mediaeval Europe, and only end-grain blocks can stand the pressure of an iron press.
In China, only plank blocks had been used for printing. The plank block is softer and easier to carve and is also easier to procure, and it can be obtained in larger sizes. Various kinds of wood can be used for blocks so long as it is not too hard, too soft, too knotty or too fine-grained. In order to withstand prolonged soaking without warping or splitting, most of the blocks used for printing in China were made from the wood of fruit trees like the date, pear, lychee etc. Woods with fine grain and obtainable locally.
The Studio of Wing Po Chai in Peking uses blocks of poplar wood (...) while Japanese use cherry wood for printing of Ukiyo-i. Poplar wood and cherry wood are too soft and easily worn out, so the printing editions are limited to a few hundreds only.
For mass quantity printing, the wood blocks should be left in water for several days until they are completely soaked before the printing process is carried out.
The ink used in the book printing was made from the soot of pine wood. Old pines were selected and cut into pieces of manageable size and put in a kiln. Soot was collected after several days of slow burning. Gum extracted from buffalo horn was then mixed thoroughly with soot. Sometimes pearl powder, the skin of pomegranate and pig's gall were added to make better ink. The best ink was made by the soot or lampblack collected from the far end of the kiln. The farther from the fire, the better soot can be obtained. At the end of Ming Dynasty, most low-cost books were printed by coal powder mixed with flour paste. Nowadays, the ink we use is mostly made from the soot of vegetable oil mixed with glue. The colours used for colour picture printing were the colours used in Chinese picture painting. They are all water-base pigments. Most of them were made from specific flowers, plants or vegetables. A few mineral colours were also used.
Paper was expensive at first. It became cheaper when new cheaper material like rice or wheat stalks and bamboo shoots had been introduced after the Tang Dynasty. Usually, better quality