Interesting that the photo is circa 1914. Mutual used it in February 1918 in an ad directed at exhibitors to consider booking the Mutual-Chaplin Specials for a repeat run. (I included a copy of the ad in CHAPLIN'S VINTAGE YEAR.)
Yes, I have seen that ad in a copy of MOVING PICTURE WORLD on the Media History site. It's a wonderful photo. I love being able to see those old ads for the Mutuals--they were so well-done. This Hartsook session is probably closer to circa 1915 actually. I have never been able to find a definite date for these photos.