This image shows port side, upper deck, midship of the Mikasa.
You can see one small anchor, four gun ports for 12 pounder gun, one ash shoot, and one entrance.
There are same things on her starboard side, but positions of the gun ports are different.
[Comparison between port side and starboard side*,
the image of port side is rotated 180 degrees for comparison. ]
The ash shoots and the entrances are respectively on symmetrical positions about the center line of the ship.
However, outlines of gun ports #7, #9, #11, #13 (starboard side) are shifted ahead of outlines of gun port #8, #10, #12, #14 (port side), respectively, although these guns seem to be on symmetrical positions about the center line.
[Midship of the Mikasa]
Positions of gun ports, ash shoots, and entrances in the drawing are based on measured values by me onboard the Mikasa.
* You may notice that positions of the davits astern are not on on symmetrical positions. That's right, but the difference may be seen too much due to difference between shooting angles of the photographs.