Your guess is as good as mine for the top one, could well be for use in torpedos, but I can't make out how. The characters to the far right are "For use with Type 3" - there was a Mod. 3 for the Type 91 torpedo, but I'm guessing with that. The characters just to the left of those, inside the label area, are "1400", "1200" and "1000" - range? The characters at the other end, just inside the left-hand end of the scaled area, are "Enemy Speed", but as the coloured tracks go up to 160, I'm assuming the tracks are for angle on the bow, towards / away from the aircraft, not the speed of the ship. Maybe the whole thing is meant to clip onto some other kind of register, which would then allow the crew to determine the correct drop range for a target moving, say, at 20 knots angled 15 degrees away. Dunno.