I think everyone needs a good whistle, and this is a lovely, rare, special feeling one, finely carved of horn with a perfectly fitted inset wood mouthpiece, ready to blow! Inside is a small cork ball, which gives a bit of a warble to its strong, high--but not too high--pitched sound. With a hole at the tip for threading on a chain to wear around the neck and keep at the ready. 

2 3/4” l x 15/16” d and in excellent condition. 2nd half 19th c. I believe, possibly made by Dixon & Sons. (There is a great website dedicated to antique whistles: https://www.whistlemuseum.com/)