I did some further research and I’d have to guess the mid 1900s (between 1900-1910 that is). But I forget that many of the photos on here are from English posters and that English and American fashion, while closely related, wasn’t always on the same page during the 20th century. The younger man in the back appears to be wearing a collar very similar to Arrow’s Addison, which was popular here in the U.S. up to at least 1908 (actually, the only three advertisements I can find are from 1908 – Sears and Arrow itself). But Jim’s right, it appears to have died out shortly afterward and collars were square and straight edged again. The older man’s collar would indicate pre 1908 as well. The woman’s pince nez eyeglasses were popular in America from about 1900-1920. Her dress – which threw me off at first – appears to have the collar, waistline and sleeves of Edwardian fashion, 1900-1910.