John , I have confused James with Schenkl, disregaurd rank and method of death. I used to have an almost photo memory, 40 years ago, now I'm like a computer with a virus:)
1863 Date and info on Sabot secret are in Bell's, along with part about not even known to wife. I notice the patent reads like a grocery list, and contains no proportions , timing, or steps, which was probably the "secret". I think she had a good lawyer, it's general enough she would get royalties on any paper sabot design. According to Jack, it wasn't just swelling problems after his death, but sometimes also too hard to take the rifling, or too soft and swelling, implying that something wasn't done as consistently as previous. I though about the workers and quanity involved, but no one seems to know the formula even now, so there was a step involved he didn't share or they kept it well for him. Some compounds are very specific, one component added at wrong time or quanity changes the whole batch. Could also have just been a quality control issue. I don't know more