Removing Linoleum From Hardwood floors

I recently purchased a house built in 1900 - during the 70's, the hardwood floor was covered by linoleum tiles w/ tar underlayment and water soluble adhesive (subsequently covered by carpet). While I think that dark brown and cream tiles are a beautiful addition to any home (it gives that quaint bowling alley feel), I'd prefer to restore the wood floor...

While I can remove the tile, the tar paper was very difficult to remove: I perforated the tar paper w/ a wallpaper scoring tool, and then used water to dissolve the glue underneath. It was a VERY slow process (and water of course damages the wood, which had been scuffed to help the adhesive stick) Is there an easier way??? I've heard about heating then scraping, but that may put the tar into the wood grain? please help!