Andrew Nethercott Antiques has dated this piece to the 19th Century.

The thumb screw alows the top to be set at different heights.
The stand could be adjusted in height with the small side handle, which when loosened allows a central wood stick to be pulled up from inside the base.

All in very good, sound condition, insignificand chips, warps and stains.
Un faded well figured rosewood, original lead ring weight in base.
Diameter of base 5,7/8" or 150mm
Diameter of top 5,1/4" or 133mm
Height 7,1/4" or 184mm, extended 9,1/4" or 235mm,
weight 732 grams.
Andrew Nethercott Antiques has dated this piece to the 19th Century.
Works of art, collectables, scientific and decorative antiques from the 17th - 20th century
You can view the stock and full dealer information on the Andrew Nethercott Antiques Profile Page