Posted: 13/12/2014 at 06:53
Hi Odis - I've not grown Black from Tula, but I have grown other heirloom beefsteak varieties and many or even most of them are dense and fleshy inside just as your picture. The size you show looks fine to me - Tula is described as having smallish 3" - 4" fruits.
I don't know whether Tula is usually a large plant or whether there was a problem with the growth. When you say the plants were sickly - can you tell us more? Have you any photos of the leaves and stems?
I wonder if the plant in the pot was too dry - at the roots or even if the atmosphere was too dry and hot for the flowers to set fruit?
Italophile is a regular contnributor here and is very knowledgeable about tomatoes - hopefully he will be along and can shed more light on this for you.