This is a great example of an antique bird scarer.  The handle and main body are made with rosewood which is really unusual for these bird scarers a real sign of quality.
These rattles when swung rapidly emit a strong clacking sound as the wooden tongue rattles over the wooden cog. This bird scarer is still in working order. 
British, circa 1880
It measures 17.5cm w x 6cm h x 2cm d.