Here is a photograph from a different angle that shows the wooden section of the old #1 substation at Boylston (on the right) and Second St. (on the left)
(I noticed on the
Baist maps that Second Street is also labeled Lake Shore Avenue)
7/01/1912
http://hdl.huntington.org/cdm/
You get a glimpse of the new station at the far right edge of the photo. At left, a street-car whizzes by. No idea who the man is.
__