Adams Morgan didn’t exist in 1888. Back then it was called Washington Heights as many of the other uptown destinations began their lives similarly: Cleveland Heights, Friendship Heights, Massachusetts Avenue Heights. If you’re curious to know the story about how it came to be Adams Morgan, read this story from a while back.
Here is the same area today on Google Maps.
We also have a great map showing Adams Morgan when it was very rural, which is hard to imagine today.