Never go full fish-eye.

Here is a fish-eye map of troop positions in Chattanooga in 1863. I find it to be a strange presentation of information. Perhaps I am just old fashioned in liking my troop position maps to be aerial views, even a bird's-eye view, but I never considered the fish-eye view. When looking at it as a whole, several trees are the dominant objects. Lookout Mountain is placed at 8 o'clock, so the fish's perspective was one from Missionary Ridge. Why this map adheres to the standard alignment of the cardinal directions, I have no idea. It seems that if you are getting this fanciful, might as well put North somewhere near 3 - 4 o'clock to place Lookout Mountain and Chattanooga as prominent features to those reading the map with human eyes.

All fun aside, it is an interesting graphic. I am not sure if it was a particular style of the time used for eye candy in publications, but expect so. You can get a high quality image of it from the Library of Congress' American Memory site to zoom in and explore. If you haven't spent time on the site, you should. Plenty of maps and photos of Chattanooga and the region. High quality (as in 160Mb) TIFFs are available of the photographs in the collection as well as the high quality map files.