We have a late 1800's house and redoing our kitchen which had two layers of vinyl on the floor, we started removing it and then found a beautiful wood floor with a heavy covering of black tar on top. We spoke to several sanding folks and they either use a big floor sander to get it off (and alot of sandpaper) or use a short 1" scraper that you pull toward you to peel it right off. However one of them told us this trick. You maybe in luck like us. Some tar believe it or not is water-soluble. Try it in first in a small not too obvious section. We poured water on it, let it sit and it came up much easily than just scraping it. Saves alot of time and money.