In museum of ancient history one often sees bamboo or wood strips written with characters by the writing brush. These slips are called jian, the earliest form of books in China.

The practice of writing on slips began probably during the Shang Dynasty (c.17th-11th centuryB.C.) and lasted till the Eastern Han (A.D.25-220), extending over a period of 1,600 ---1,700 years. The Historical Records, the first monumental general history written by the great historian Sima Qian (c.145 B.C.-?), consisting of 520,000 characters in 130 chapters and covering a period of 3,000 years from the legendary Yellow Emperor to Emperor Wudi of Han, was written on slips. So were other well-known works of ancient China, including the Book of Songs (the earliest Chinese anthology of poems and songs from 11th century to about 600 B.C.) and Jiuzhang Suanshu (Mathematics in Nine Chapters completed in the 1st century A.D., the earliest book on mathematics in the country).

Excavations in 1972 in an ancient tomb of the Western Han Dynasty (206 B.C.- A.D. 25) at YinqueMountain, Linyi, Shandong Province, brought to light 4,924 bamboo slips. They turned out to be handwritten, though incomplete, copies of two of China's earliest books on military strategy and tactics: The Art of War by Sun Zi and The Art of War by Sun Bin. The latter had been missing for at least 1,400 years.

To write on bamboo or wood slips was no easy task. Take bamboo slips for example. Bamboos were first cut into sections and then into strips. These were dried by fire to be drained of the moisture of the natural plant to prevent rotting and wormeating in future. The finished bamboo slips run from 20 to 70 cm in length. Judging from those unearthed from ancient tombs, royal decrees and statutes were written on slips 68 cm long, texts of the classics on 56-cm-long slips, and private letters on 23-cm ones. The brush was used in writing and, in case of mistakes, the wrong characters would be scraped off by means of a small knife to allow the correct ones to be filled in. The knife played the same role as the rubber eraser today.

Writing on bamboo or wood slips was done from top to bottom, with each line comprising from 10 to at most 40 characters. To write a work of some length, one would need thousands of slips. The written slips would then be bound together with strips into a book. Some books were so heavy that they had to be carried in carts. In some cases the blank slips were first bound into books before they were written on.

An unofficial story tells about Dongfang Shuo (154-93 B.C.), a courtier and humorist, who wrote a 30,000-character memorial to the Western Han Emperor Wudi, using more than 3,00 slips. These had to carried by two men to the audience hall

Legend also extols the hard work of the First Emperor of the Qin of 2,200 years ago by telling that he had to peruse and comment on 60kilograms of official documents every day. This may not be so astonishing as at first hearing, when one recalls that the passages were written on wood or bamboo slips.

Heavy and clumsy as they were, ancient books of bamboo and wood played an important part in the dissemination of knowledges in various fields. They were in circulation over a long period until gradually replaced by paper which was invented in the Eastern Han Dynasty (A.D. 25-220).