Liberty Pewter Sketch Book, Westminster City Archives, n.d., p. 58, no. 0370
Adrian J. Tilbrook, The Designs of Archibald Knox for Liberty & Co, London, 2000, p. 106, fig. no. 85 (for a version without copper)
Stephen A. Martin, Archibald Knox, London, 2001, p. 239 

Overall in very good condition. The surface of the pewter has a wonderful patina throughout. The pewter is in good condition, with minor surface scratches consistent with age and gentle handling and minor evidence of tarnishing to the recessed portions of the design. The dial appears to have been covered with a later clear finish that has lightly flaked off over time and is not visually distracting. The clock face with a very minute enamel loss to the interior edge, below the number 3. The two lower circular decorative enamel elements with two minor areas of restoration, visible in the catalogue illustration. The proper right medallion with noticeable wear and rubbing to the upper edge, visible in the catalogue illustration. With a key. The enamelwork presents with rich coloration and nice luminosity.
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.