Last updated: 12-10-2021
The gibbon, a small, arboreal ape endemic to East and Southeast Asia, is known for its ethereal song and spectacular displays of acrobatics. Anyone who studies this primate, be they primatologist or scholar of history, mythology, or art, should own a copy of Robert van Gulik‘s (1910-1967) The Gibbon in China (1967). Though brief, this work is an amazing survey of historical references, poems, folktales, and art spanning over 3,000 years from the Zhou to Qing dynasties. Originally called a “white ape” (baiyuan, 白猿), the primate was thought to possess Daoist magic and secret knowledge (such beliefs influenced Sun Wukong). The Gibbon in China is out of print and hard to find, and available copies are prohibitively expensive. So I am thrilled to share a PDF of this wonderful piece of scholarship.
I would have included a digital file of the original “grammophone record” of gibbon calls, but I don’t have the know-how or equipment necessary to digitize it. I may add the file in the future.
The scan was produced with an overhead document camera. The glossy pages made scanning somewhat difficult. I had to use a soft, indirect light source. In addition, the print on numerous pages was already really faint due to the book being a photocopy of the original typescript. Therefore, sections of some pages appear blurry but still readable. The original file was 247 mb. I compressed it to a smaller file. I can provide the larger file upon request.

A gibbon soaring through the treetops. Photo by Sachin Rai. A larger version can be found here.
Description from the preface
The gibbon … was the traditional, purely Chinese symbol of the unworldly ideals of the poet and the philosopher, and of the mysterious link between man and nature. The gibbon initiates man into abstruse sciences and magic skills, and it is his calls that deepen the exalted mood of poets and painters on misty mornings and moonlit nights.
From the first centuries of our era on, Chinese writers have celebrated the gibbon in prose and poetry, dwelling in loving detail on his habits, both in the wild and in captivity. Great Chinese painters have drawn the gibbon in all shapes and attitudes; till about the 14th century from living models, and when thereafter the increasing deforestation had reduced the gibbon’s habitat to S.W. China, basing their pictures on the work of former painters and on hearsay. So important was the gibbon in Chinese art and literature, that he migrated to Japan and Korea together with the other Chinese literary and artistic motifs, although Japan nor Korea ever belonged to the gibbon’s habitat.
The gibbon thus occupies a unique place in Far Eastern culture, it being possible to trace the extent of his habitat, his appearance and his mannerisms for more than two thousand years. Therefore I thought it worth while to try to assemble these literary and artistic data, for the reference of orientalists, zoologists, and animal lovers in general. The results are embodied in the present essay.
The book begins with an introduction, describing gibbons and their habitats as I came to know them during many years of daily association. I have illustrated my observations with photographs of a few of my own gibbons; a key to those will be found at the end of the volume. It is hoped that these introductory remarks will supply the reader with the general background, and provide him with the material for comparison with the Chinese literary and artistic data contained in the body of this book.
The main text is divided into three parts, treating the subject-matter in chronological order. Part I describes the earliest data available, from ca. 1500 B.C. till the beginning of the Han dynasty, 202 B.C. Part II deals with the early centuries of our era, and gives a general picture of the gibbon as he appears in the literature of the T’ang dynasty which ended in 907 A.D. Part III is mainly concerned with pictorial representations of the gibbon in the art of the Sung, Yuan and Ming dynasties. The survey ends with the beginning of the Ch’ing dynasty, in 1644 A.D.; for after that date the gibbon became so rare in China that what is written about him is largely repetitious. An appendix gives a brief account of the gibbon in Japan.

A pair of mated gibbons. A larger version can be found here.
Book link
Update: 12-10-21
I’ve posted a piece about a folk Taoist white ape god related to Sun Wukong.
The White Ape Perfected Man: Sun Wukong’s Divine Double
Disclaimer
This has been posted for educational purposes. No malicious copyright infringement is intended. If you like the digital version, please support the official release.
Citation
Van Gulik, R. H. (1967). The Gibbon in China: An Essay in Chinese Animal Lore. Leiden: E.J. Brill.