Identification
ID in this catalogue SL Louvre N 781
Type L-shaped 
Current Location

Musée du Louvre, Paris.

Sully Wing, Ground Floor, Room 6, "Writing and Scribes", Vitrine 6 "Weights and Measures" (Louvre Atlas database) 

Catalogue Numbers N 781 
Provenance Unknown 
Date 1400-1350 BC (Louvre Atlas database) 
Dimensions H 49.8 mm, W 31.8 mm, D 18.5 mm (Louvre Atlas database) 
Material Wood (Louvre Atlas database) 
Markings and inscriptions The reconstructed scale uses lines across the width of the scale in the 3:6:9:12:15 length ratios. The gnomon block contains a hole and vertical reference mark for a plumb bob on one side. "Amenhotep III offering Maat to the sun god; on the short side [opposite the plumb bob mark], the goddess Sothis "mistress of the year" (Louvre Atlas database)  
Notes This is the gnomon part of an L-shaped sundial. It is on display with the missing parts reconstructed in modern material. The reconstruction also includes an ancient-looking plumb bob. The original relationship between the plumb bob and the gnomon is unknown. 
Literature

Borchardt (1920) p. 32 ff.
Salmas (2014)

Images

Three images are available in the Louvre Museum's Atlas database here