public void disconnect(Tile t){
		if (t == null){
			throw new IllegalArgumentException("Can't disconnect null");
		}
		if (t == tile1){
			tile1 = null;
		}
		else {
			tile2 = null;
		}
		setChanged();   //this is so observers can detect if it is stranded, and remove it if they like
		notifyObservers();
	}