Inventory no. 46931 - Former Display Label
Blank for an ASTRONOMICAL &
DIALLING INSTRUMENT, ?Persian
?19th cent.
No inscriptions. Brass. Overall
diam.: 85 mm; diam. of central hole:
40 mm; thickness: 4.5 mm.
Probably a blank for an instrument
with linear and trigonometric scales
for dialling and astronomical purposes,
and for determining azimuths of the
Qibla (direction of Mecca).
Two such instruments are shown in
the Islamic section of the sundial cases.
Like those instruments, it has holes
drilled in the plane of the disc at right
angles to each other. Threads passed
through the holes define the centre, so
that the instruments could be used as
templates for laying off scales.
[69-217/1] Purchase