Ardsley made no comment, but continued his exposition.
“It wouldn’t require a large dose to kill a man. Curare contains various alkaloids. Paracurarine and protocurarine are amongst them. A quarter of a grain of protocurarine would kill a ten-stone man quite easily. There was far more than a fatal dose of curare on that dart.”
“Can you tell us anything about how the stuff comes on the market?” Sir Clinton inquired.
“There are three brands of it to be had,” the toxicologist explained. “Para curare you can buy in bamboo tubes; calabash curare is packed in gourds; and what they call pot curare is sold in earthenware pots. The stuff’s a crude product, you understand. One specimen differs from another to some extent, though not materially for most purposes.”
“You have some of it in stock yourself for your experiments, perhaps?”
Ardsley smiled rather grimly.
“A man isn’t required to incriminate himself, is he? But I don’t mind admitting that I have some of the stuff. You could have found that out for yourself by examining my returns under the Act, you know, so I lose nothing by frankness.”
Sir Clinton acknowledged the underlying meaning of Ardsley’s words by a faint shrug of his shoulders, a completely non-committal gesture.
“You practically told me you had it, there in the laboratory,” he reminded the toxicologist. “What’s more important at present is to know if anyone else could have had access to it.”
Ardsley reflected for a moment or two before speaking again.