Jerry Robinson (along with Dick Sprang) was one of the two major Batman artists of the early 1940s. As I mentioned in a recent post, Robinson was the master of light and shadows. Here are some examples from Detective #76:
Characters outside the light portrayed in purple? That's Robinson's signature; there are probably a dozen examples of it in this issue alone. Check out this night-time street scene:
Notice the nice little details there; the storm sewer, the manhole cover, the car or truck coming into the picture from the left, the small blotches of light in the inky (literally in this case) darkness.
Like a movie director, Robinson knew where to place the camera:
More terrific shadow work here:
Notice how the coloring on this panel conveys the three-dimensionality of the city:
The lighter, pastel blue in the background makes it clear it's behind the more solid blue which is behind the purple building. It's the same concept that ACG would exploit years later in its "TrueVision" 3-D comics.