First one of these I've ever seen.*
In preparation for photographing this unique item made by William Scagel, 'Grandfather of modern custom knife-making' I researched a bit about corkscrews, their history and such.
This simple-appearing style is called the "direct pull" for obvious reasons. What's not so obvious is that Scagel took the high road and forged a proper worm designed to pull the cork without breaking it apart.
Though the stag has shrunk a bit through the decades and brass is no longer considered high end for fittings, this would have been a very classy accessory in its time. As such it may have been part of a set or group of commissioned items that might have included kitchen knives or tableware, or possibly one of Scagel's excellent tin lined copper pots for an ice bucket (to chill the uncorked wine).
*James R. Lucie collection