Howdy Tortoise,
Maybe you have already split the log by now? But, if not...
My dad showed me how to split a log. (He is a woodsman from the OldSchool).
He pointed out the importance of "training" the crack at the beginning.
First, on the end of the log, draw a line through the center where you want the split to be.
Then, with a hatchet, score the log along that line up and down by giving the hatchet a good tap and then moving the hatchet along the line, a little at a time, giving it a good tap each time you move it. You do this a number of times. And, after a short while the end of the log will have an actual, small visable crack along that line. And, once the crack is established across the diameter of the log, you've "trained" the log by giving it a straight-line crack to follow. Doing this will greatly improve your chances of getting a good clean split the whole length of the log.
You can now go at it with a heave hammer and splitting wedges.
I hope this was helpful,
Canoe