I’ve decided that Portia is going to suffer her injuries (that lead to the hearing and speech loss) via an explosion of a land mine.
The specific land mine in question will be activated via tripwire run between railway tracks.
It turns out that mines were used in the U.S. to derail at least two trains during the Civil War, so my scenario is feasible. I’m trying to decide between the 1kg Soviet EZ Mine and the 5kg Tellermine 29 (which literally feels like overkill) because both existed in 1932 when this casebook occurs.
One person will be killed, Portia will be injured, and one other person will lose a limb from this blast, making me think the 1kg mine is (Gods help us) sufficient.