On the back of the image, is a stamp printed "September, 1922." It is part of the Phila Aero Collection as that is stamped on it as well. I live in the Philly area and have seen the Hagley stuff (cool collection). I noticed alot of their stuff is mid to late 20's and that is why this image stood out for me (also the angle on which it was shot).
I am working on a different project, with a slight connection to Merion, and was attempting to show the time period for context of the era while purusing the collection. I merely stumbled upon this stuff.
You could be right, it might be later than '22 and the person who marked it made a mistake (we'll never know). But the image is in a book of images that are sequential in nature, the preceeding image before this one, is of Haverford College (of the same vintage, marked '22) and the image after it is of the Delaware River Bridge (now known as the Ben Franklin Bridge).
Why that is significant is that contruction began on the bridge in January of '22 and finished in '26. I took these images with my iphone but happen to have my portal scanner with me too (which I did scan them). If you PM me your email address, once I download them, I can send to you. Again, I am not sure of the quality because I was scanning blind (no laptop with me).
Ben Bridge here:
http://twitpic.com/d34sxm