I know this isn't the tomato forum but I wonder if anyone here knows if there is any database or resource of any type to identify heirloom tomatoes.

The reason is, my Grandpa (who passed away last year in his late 80s) left me a shoebox full of tomato seeds, collected every year from a lineage of tomatoes from his family farm pre-1920s. He saved seeds every year, worried that they would hybridize and not be true anymore, but I have since learned that this is unlikely to happen in tomatoes. I have grown them a couple of times and the fruit is very red and flavourful, the only problems are susceptibility to cracking (thin skins) and blossom end rot.

Anyway I would like to know what they are, if they are a formerly commercial variety or what... any advice appreciated.

-Gillian