Backspin irons came in a variety of formats.  Most had deep corrugated or ribbed grooves laid out in various patterns. But not these two clubs. And lest you think somebody just pounded in some deep dots into the face after the fact, both of these irons were marked "Bakspin" on the head by the manufacturer. And both have distinctly concave faces top to bottom. (These clubs appear to be made by MacGregor but marked for 2 other retailers to sell.)

The mashie has hand struck, deep oversized dots punched into the face at a diagonal from the sole, and smaller dots down the center of the face.  The back of the head is clearly marked "Warranted Hand Forged Bakspin OVB Mashie Niblick" and the sole is stamped "Mashie."

The mashie niblick also has hand struck, deep oversized dots punched into the face along the bottom. The back of the iron reads "Hand Forged V.L. & A. Special Bakspin Mashie Niblick."

These two irons are the top 2 irons in the group image.

The 37 3/8" shaft in the mashie niblick is original as is the leather-wrap grip. 

The 37 1/4" shaft in the mashie is original as is the leather-wrap grip.