The Gimmel Flask by Douglas Clark
The senior partner in the firm of Hardy, Williams and Lamont, auctioneers and estate agents in a quiet East Anglian town, dies soon after lunch one Sunday.
The autopsy reveals poison as the cause of death, but the poison in question is a now virtually unobtainable substance called croton oil. The police send out a general call. Every pharmacy in the country is visited; not one of them stocks croton oil. Nor does any drug wholesaler, or any hospital dispensary. The extraordinary thing about croton oil is that in the 19th century, before its deadly properties were fully realised, it was—in diluted form—in regular use as a purge, for humans and animals.
The oil, obtained heaven knows where, was apparently slipped to the unfortunate Hardy in his salad oil bottle—he liked to mix his own dressing at table—and now the bottle has vanished: stolen, presumably, by the murderer, who hasn’t left a clue.
In some despair, the local police call in the Yard, and soon we have the subtle Superintendent Masters and the aggressive Inspector Green on the scene: Douglas Clark’s regular team, and we are launched upon another of his fascinating medical whodunits.
Douglas Clark was born in Lincolnshire, 1919. He wrote over 20 crime novels and under other names, including James Ditton and Peter Hosier.