The window design and arrangement had that classic 1930s industrial office look, which the Verizon building's base (the bottom 8 stories) has deliberately paid homage to. The Verizon building gives a big nod to the Analex building in both its window design and its massing. When I was a kid in the 1950s, the Analex was highly visible as you rode on the GL or OL coming up out of the Haymarket portals up the elevated line to North Station. It was impressive, massive and taller than anything in the area. And like I say, the design had that really clean, no-nonsense industrial look. I also liked the detailed yellow brick work on all of the exterior. Unfortunately, it did deteriorate in the 1970s and 80s with portable AC units in the windows, etc., but back in its day it was great. Photos of it are very scarce online.
Edit: added a couple of photos of the Analex building:
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