Illustrated manuscript on paper, entitled "Hansho [or Bansho] kai" ["Ryukyu Potatoes Explained"]

Six pages of color paintings of species of sweet potatoes. 14 folding leaves. 8vo (267 x 190 mm.), orig. decorated semi-stiff wrappers, stitched as issued, manuscript title label on upper cover. [Japan]: late Edo.


Sweet potatoes are one of the glories of the Japanese table. The author of the text of this finely illustrated manuscript was the Nagasaki resident Tokitane Kohiga, mathematician and scholar of materia medica. The text was written in October 1805, and this is surely a later copy.


The sweet potatoes of Ryukyu (today, Okinawa) are famous. The potatoes came from China and began to be cultivated in Ryukyu in the early 17th century. By 1611, their cultivation extended to the Satsuma Domain and, several years later, these sweet potatoes appeared in Nagasaki. Sweet potatoes have remained an important crop throughout Japan, especially in times of famine.


Kohiga describes the importance of the sweet potato in the Japanese diet and comments that its cultivation was widespread, not only in Japan but in many other places, including the Philippines, China, and "the Western world." He comments on their superb nutritional value and provides extensive details on cultivation, stating that sweet potatoes grow equally well in rich and poor soil.


Kohiga gives instructions on how to successfully store the crop after the harvest. This is followed by many recipes, including how to process sweet potatoes into flour for dumplings, and how to make shochu, the alcoholic beverage, from fermented sweet potatoes. The stems and skins of the potatoes were fed to horses and cows.


The fine illustrations depict six species of the sweet potato, showing each one's leaf, the entire potato, and a cross-section. The six species are: Shiro imo, Mitsuba imo, Ninjin imo, Sakura imo, Satsuma imo, and Kitsunae imo. For each one, the author furnishes comments on its names, size, weight, ease of cultivation, taste and texture, appearance when cooked, best cooking methods, and recipes for particularly good dishes.


Following the illustrations, the author provides four additional detailed regional recipes. An example is for the Mitsuba imo: julienne the potato, season with sesame oil, mix with flour and seasonings, and deep fry in oil.


Fine copy. Minor worming.