I have no idea but, to get back to my point, slaves(blacks) were not welcome in the north and laws were passed that made this well known. The underground railraod, for example, ran to Canada. Keeping these facts in mind it is my opinion that the North was not fighting so much to free the slaves as they were fighting to prevent the spread of slaves (blacks). Have you ever read anything of this nature? It is a point to ponder isn't it?
GP