Just to let you know, I am thinking on your problem. I have a friend very versed on Victorian Homes heading to my house today and I will pick his brain.
I like Mike Damiano's step one approach for two reasons. First,if they are lined, that means they were meant to handle wood buring fires. If they are not lined, then, as was the "up to date method" of the day, they may have been intended to handle gas. Not being an expert on dates, I am not sure when gas became the thing to do, but I do know that many Victorians were retro'd with gas. If your house happened to be constructed during that transition period, then it is possible it was meant to handle only gas combustion methods.
Let us know about the chimney. Is it lined and intended for wood burning fires? This is a good step to solving the problem.
I might also ask if there is any evidence of a furnace in the basement, or a coal chute? Coal burners were also common of this era.