NATIONAL LIBRARY OF MEDICINE, 8600 Rockville Pike Bethesda. Open Monday through Friday 8:30 a.m. to 9 p.m., Saturdays to 5, through May 22.

How intimately can a man shre in the birth of his child?

Among the Huichol Indians of Central Mexico, a father would climb into the rafters with a rope tied around his scrotum -- to be pulled by the mother while she delivered: Together they shared the pain and ultimate joy of childbirth.

Records of the birth customs and medical knowledge of America's pre-Columbian natives are now fragmented and scarce. With a tragic efficiency, the Spanish conquerors and missionaries of the 16th century destroyed many of the elaborate hand-painted manuscripts of the Central American Indians to blot out their "pagan" history.

Using the available sources, however, the National Library of Medicine has put together a small but surprisingly provocative sampling of materials the permit a glimpse of pre-Columbian medical customs. The exhibit on display in the library's lobby for one more week, includes ancient sculpture, photographs, skeletal remains and a partial reproduction of an Artec manuscript.

At the heart of the exhibit is a novel collection of 40 pre-Columbian ceramic figures dating from about 300 B.C. to 1000 A.D. Although a few of the sculptures may strike some viewers as grotesque, they all carry a common thread of medical information that unveils childbirth, disease and death among artistically sophisticated peoples whose cultures no longer exist.

The exhibit also focuses attention on the central figure in Native American medicine, the medicine man or shaman. Combining the roles we know as priest and physician, the shaman would administer herbs and other remedies to his patients or, at times, consume psychoactive plants or mushrooms himself to "speak with the spirits" and help his patients deal with disease. The powerful role of the shaman in Indian society required an understanding of physical, psychological and supernatural influences on human behavior.

In addition to providing an introduction to the medicine of the pre-Columbian Americans, this exhibition is also a good reason to visit our own National Library of Medicine, one of the world's great-storehouses of medical knowledge. Tours are given at 1, Monday through Friday.