We all know famous people who were murdered by poisoning from ancient times till today. I am not interested in this, I am more interested in average people killing their spouses, relative (maybe friends, enemies) with poison.
Up till early-mid 20th century poisoning was the perfect murder:
- no obvious sign;
- many poisons were very hard to detect even when suspected;
- easy access even for the common people as many household chemicals contained them.
Unfortunately, I have found very few documented cases (most probably because of the difficulty of study it retrospectively). The most famous one is maybe the AngelMakers of Tiszazug after WWI, where wives murdered their husbands and other relatives in large number. There are some interesting differences between the English and Hungarian version of the wiki, including the estimated number of victims (50ish vs 300ish), and Hungarian wiki clearly mentions that similar (less famous) cases happened in the neighborhood and other part of the country, too. Authorities generally tried to hide these cases, to avoid scandal, which I guess makes their research even more difficult.
So the question: do we have any estimation, how common form of domestic murder poisoning was?