I'm hoping someone will use the online perforation gauge and share their measurements here in the forum please. The stamp is scanned at 1200 DPI.
Petert4522 - I prefer the online perf gauge as others can measure and share their measurements. I have several perforation gauges - "phila combi box" , a "white ace postage stamp perforation gauge", a "Precision US Specialty Multi Gauge" and a S.G. gauge somewhere around here lol.
Galeoptix - The double impressions are along the top frame, in Postage & Revenue, top left, top right... in misc areas. It's quite hard to miss.
You stamp is perforated 14.
I thought you would correct me and say that my stamp was 15 x 14 as in 1911 Stanley Gibbons GB 283. This stamp is not perforated 14.