He is there in the morning, I found him on friday around 10 am
Because the volcano on Cinibar Island erupted.
In his gym
To get to the seventh gym leader, Blaine (fire-type gym leader), you have to go to the Seafoam Islands. As soon as you enter, go up the first ladder you see. Blaine's gym is incorporated in the Seafoam Islands because of the volcanic eruption on Cinnabar Island.
Blaine is the gym leader in Cinnabar Island. When you get to Cinnabar Island the door to the gym is locked, you need to go to the Pokemon Mansion to retrieve the key. Once you have it you get to the gym and battle Blaine to get your seventh badge.
seafoam islands; 15th gym
Blaine.
To get to Blaine, he is on cinnabar, but the last gym leader... He is in one of the towns once you defeat Blaine, I think it was Viridian or Vermillion. =)
Blaine's gym is in the Seafoam Islands
Blaine's Gym is in Mahogany Town.
He doesn't rebuild his gym. He moves to the Seafoam Islands.
volcano badge
The seventh gym (Blaine's) used to be on Cinnabar Island. After the town was destroyed by the volcano, Blaine has relocated his gym to the Seafoam Islands. Just Surf east of Cinnabar, and you will reach him.