I'm pretty sure I first read about John Rhode at In Search of the Classic Mystery. This blog reviews tons of mysteries, old and new, but mostly old. I found The Claverton Affair, a Perennial paperback for $2.50 at one of my local used book stores. It always feels good when you discover an elusive book at such a low price.
Dr. Priestly hasn't seen his old friend John Claverton for almost a year, so he gladly visits him at Claverton's request. Claverton has been ill, but he seems to be recovering nicely. He wants to tell Priestly something but never gets around to it because his doctor, another old friend, arrives. Claverton dies suddenly only a few days later.
Because of an earlier gastric attack, Priestly is concerned that Claverton has been murdered with arsenic. But testing reveals no arsenic, or any other poisons. His will surprises his heirs. He leaves the bulk of his estate to a woman and her daughter. No one has ever heard of them. He further stipulates that one of his other heirs will inherit more money if he marries the mysterious daughter.
Claverton had asked his niece, a nurse, and her mother, from whom Claverton has been estranged, to come nurse him through his illness. They move in, although Claverton refuses to see his sister. They both inherit something, but not what they had hoped for. Dr. Priestly suspects them of, if not murdering Claverton, speeding along his death.
It takes a while, but Dr. Priestly figures out who murdered Claverton and how. I had begun to suspect 'how' fairly early in the book, not all the details, but the general gist of it. I wasn't sure, though, who had done it.
I enjoyed the book and will gladly read others by Rhode if I happen on them.