"Inclination Compass By Deleuil - 1850s'"
Unusual inclination compass bearing the signature "Deleuil Paris" dating from around 1850-1860. The instrument was made by Louis-Joseph or Jean-Adrien Deleuil, the father or the son. Mounted on a round foot with three wedge screws, a brass rod supports a circle divided into four times 0-90 degrees. In the center a needle gives the angle of inclination, that is to say the angle between the horizon and the earth's magnetic field. The circle measures 13.5 cm in diameter and the instrument 27 cm in height. The needle is no longer perfectly magnetized. Otherwise, good condition. 
Le Magazine de PROANTIC
TRÉSORS Magazine
Rivista Artiquariato