circa 1870's mystery mounted baseball photo

[bbpostcards]

Here's a mystery that someone might help to solve. The caption written on the mount reads "Alaska BBC." The number "16" is at the bottom of the image. Written on the back is "pp. 1779" and a few stray notations. A New York team in that time period was called the Brooklyn Alaskas. As well, a Hawaii newspaper in 1880 refers to the Alaska BBC (probably the U.S.S. Alaska, which stopped there in 1880). An "A" is clearly visible on their uniforms. At the extreme left is what looks like a small flag on a pole. The image is quite brown in tone, so I've included a manipulated version of the picture to make it clearer. Any ideas?