拍品专文
Danfrie invented the graphometer, and published a description of it in his Declaration De L'Usage Du Graphomètre (Paris, 1597). It was a simple and economical instrument that could be used to measure angles in either the vertical or horizontal planes, and, occasionally modified or improved, "it was the standard surveying instrument in France until the early nineteenth century" (Turner, p. 75). Turner also illustrates and describes the present example on p. 54, fig. 37 ("c. 1597-1606 ... may originally have had a compass set above the pivot"), and is illustrated and described by Turner and Wynter in "Scientific Instruments on pp. 155 and 157, figure 190. Daumas reproduces a engraving from the Declaration as plate 7, which shows a similar graphometer bearing the same legends on the alidades (apart from the rotating alidade, which is also marked [?]P. senestre and [?]Par. dextre) and similar foliate motifs. However, the decoration to the protractor strut is, whilst stylistically close, a different pattern. The graphometer by Danfrie held at the National Maritime Museum, Greenwich (illustrated by Daumas as plate 8) is dated 1597, and, like the present example, is signed P. Danfrie .F. The titles to the two alidades are the same (except for the star after MOBILLE), but the foliate motifs are different, and the protractor strut bears another pattern.