These big block-head putters made famous by Jean Gassiat were introduced around 1913 and made at various times by various makers during the ensuring years.  They are often called grand piano putters because they are big & heavy (for a golf club) made out of wood, and their rectangular shape is reminiscent of many 19th-century pianos there were also rectangular in shape.

This Gassiat-style putter is stamped "Ernest F. Sales Special" on both its head and 43" shaft. The shaft has nice St. Andrew's bend, gracefully curving back towards the golfer. Face depth is extremely shallow at 3/4" at the toe 5/8" at the heel.  The four lead backweights and brass plate on the sole are original. 

This club was used back in the day, but it has survived in excellent original condition.  The club has its original shaft and built-up top of the grip, which is described in an October 31, 1913 Golf Illustrated review as an "extra thickness at the top for the use of the left hand."  A quick inspection reveals how the grip was made by using a second piece of wood. This grip is one of the first "pistol grips" produced in the world of golf.

For more on Gassiat putters, see TCA2 v2 p537