Spalding's 1904-1905 Fall and Winter catalog offered two center-shafted mallet putters "manufactured from models made expressly for Mr. [Walter] Travis" (between 1900 and 1904, Travis won the US Amateur three times and the British Amateur once). The Style A had a narrow head and the Style B had a broad head.  Both putters had a brass face plate and lead back weight and a rounded toe and heel across the top of the head.

In 1906, the Spalding changed the Style A and style B putters B to the Model A and Model R, which is what this putter is.  The Model R was also a large center-shafted mallet putter. It came with a brass face and convex sole as found on this putter. Spalding discontinued the Model A and Model R in 1909.

This Spalding Model R putter offered here has its original shaft, which is faintly stamped "A.G.Spalding, Gold Medal" and original leather-wrapped grip.  It's a stylish short stick that gives every indication that it would work well even today!

TCA2 v2 p609-610.

This club is easily recognized in both of the accompanying group images.