"Then there was that indefinable connection between himself and Jack; who therefore would never let him alone; never" (184).
Jack and Ralph are easy companions early on in the story. They climb the mountain together with Simon, and there is a definite sense of camaraderie between the two older and more athletic boys. As Ralph is chosen for chief, however, and Jack is overlooked, their companionship falls into rivalry. Jack seems determined to prove his superiority over Ralph in terms of hunting, leadership, and popularity with the other boys.
Merridew was used to being in charge like when he was head chorus boy and does not like to be second best. Jack will not let Ralph alone, because he is driven to prove his dominance over the other boy. Ralph is a threat to his being chief, and because of this insecurity, Jack will not rest until Ralph's threatening presence on the island is effectively removed.
the connection was that they both had potential to be great leaders, and knew how to influence the other kids. The connection develops when they're left on the island without any adult supervision! They both are the only ones willing to take the lead and whom the other kids will listen to. Ralph gains his followers and Jack gains his. Unfortunately, one of them proves to be a chaotic dictator, while the other is a peace loving liberal! It signifies the roles in world leadership that we see today. The way in which Gandhi lead India versus the way Adolph Hitler lead Germany! Hitler felt that the best way to establish order was through chaos and lies, like jack, while Gandhi knew that order could only come through peace, like Ralph. hope this helps :)