A rare pair of imperial yellow-glazed 'dou' and covers Qianlong incised Seal Marks and Period

the matching vessels with a splayed foot rising to a waisted stem interrupted with one raised band, supporting a generously wide cup with straight sides and flat well, the domed cover surmounted by a braided 'rope' finial, the exterior molded with motifs of waves, ovals, trigrams and other archaistic designs, applied overall with a rich egg-yolk-yellow-glaze, six-character seal marks incised under the cover and the base (4)

One cover has scattered traces of black iron spots, and hairline crack from bottom of cover approximately 1 3/4 inch long. One vessel has two hairline cracks at the mouth rim, the longest approximately 1 3/4 inches along the interior (visible on the exterior as well). The opposite end of the mouth rim with a triangular saddle chip 1/2 inch long. All in overall good condition.
In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective qualified opinion.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING CONDITION OF A LOT, ALL LOTS ARE OFFERED AND SOLD "AS IS" IN ACCORDANCE WITH THE CONDITIONS OF SALE PRINTED IN THE CATALOGUE.

The present pair of dou belongs to a group of porcelain ritual vessels placed at the Altar of Earth or the Altar of Agriculture in Beijing. The color yellow was sanctioned for both altars. Ritual vessels used at the altars of the four Cardinal Directions -- the Altar of Heaven, the Altar of the Moon, the Altar of the Sun and the Altar of Earth -- were all of similar form but coated in blue, white, red and yellow glazes, respectively. Margaret Medley in 'The Illustrated Regulations for Ceremonial Paraphernalia of the Ch'ing Dynasty in the Victoria and Albert Museum', Transactions of the Oriental Ceramic Society, vol. 31, 1957-59, p. 100, notes that the Qianlong emperor issued a decree in 1748 that porcelains of the appropriate color were to be used at certain altars and temples.

The surface decoration found on this vessel is after that of the lacquered wooden vessels used at the Temple of the Ancestors during Qianlong's reign. Josh Yiu mentions, in his notes on the set of white-glazed ritual vessels that include a pair of dou, a pair of fu, a pair of xing and a pair of gui from the Qing court collection and now in the Palace Museum, Beijing, included in the exhibition China. Three Emperors, The Royal Academy of Arts, London, 2006, pp. 396-397, that the emperor ordered the Grand Secretaries to consult classical texts when designing the ritual objects and that the shapes ought to reflect those of archaic ritual paraphernalia. The various ritual vessels were illustrated and described in the 1759 edition of the album Huangchao liqi tushi ('Illustrated Regulations for Ceremonial Paraphernalia of the Qing Dynasty'). This album was included in the exhibition The Life of Emperor Qianlong, the Macao Museum of Art, Macao, 2002, cat.no. 11, together with a bamboo dou and a wooden fu both covered with yellow lacquer, cat.nos. 11.1-2.

Although yellow-glazed ritual vessels with Qianlong seal marks are rare, a fu incised with a Qianlong seal mark and of the period was sold at Christie's London, 5th June 1995, lot 182, and again, 4th December 1995, lot 173. For further examples of Qianlong ritual vessels, see a blue-glazed dou and jue illustrated in The Tsui Museum of Art. Chinese Ceramics IV. Qing Dynasty, Hong Kong, 1995, pls. 44-45; a red-glazed dou sold in our Hong Kong rooms, 8th April 2007, lot 713; and a yellow-glazed gui sold in our London rooms, 9th June 2004, lot 205.