Borrower of the Night - Elizabeth Peters [73]
Tony’s breath caught.
‘One of the oldest and most commonly used poisons is arsenic,’ I went on. ‘It’s mentioned by Roman authors, if I remember correctly, and in the thirteenth century the proporties of arsenicum were discussed by no other than Albertus Magnus. We found a copy of his well-known work in the library. I think I know now who owned it . . .’
I turned to Blankenhagen.
‘As a doctor, you know that there were no scientific tests for poison till the mid-nineteenth century. Maybe one of the reasons why arsenic was so popular is that the symptoms of arsenic poisoning are identical with those of certain gastrointestinal disorders. I read that in the same book that told me arsenic remains in the body – in the roots of the hair and under the nails – for an indefinite period of time. That’s why I thought we might have luck tonight.’
‘I have never heard of it after so long a time,’ said Blankenhagen. ‘But perhaps no one ever tried. Murders several hundred years old are not generally of interest to criminologists.’
‘Get on with it,’ said Tony, nudging me.
‘The other night I just happened to find myself in Burckhardt’s room.’
‘I knew it,’ said Tony. ‘I knew it . . . We’ll discuss that later. I suppose you tripped and fell and accidentally, not meaning to do any real searching, discovered a secret panel?’
‘I found a box,’ I said haughtily, ‘which contained a quantity of greyish powder. I didn’t think of arsenic at first. The colour put me off, for one thing. I think of arsenic, when I think of it at all, as white. Either the stuff was contaminated by dust and dirt, or it had been coloured, as commercial arsenic is, to keep people from mistaking it for salt or sugar.’
Blankenhagen interrupted.
‘What you found may not be arsenious oxide, the ‘white arsenic’ of popular fiction. Elementary arsenic is grey, metallic in structure. Upon exposure to air it takes on a darker colour and loses its lustre.’
‘You can look at it later, if you want to. It’s not important; most forms of arsenic are intensely toxic. It was not the colour of the powder that alerted me. It was something else altogether.
‘The hidden drawer where I found the box was littered with the bones of dead rats. They had gnawed their way into the box, and – curiosity killed a rat. Defunct rodents aren’t unusual, but it was extraordinary that so many of them should have chosen the hidden drawer as a place in which to die.
‘Dead rats . . . rat poison . . . arsenic . . . the witchcraft-poison complex. I guess that was the way my thoughts ran, but I wasn’t aware of the progression; it just seemed to hit me all at once. And with that came another thought. What if we had been looking at the tragedy of Count Burckhardt and his wife backwards? What if he was not the villain but the victim of a plot?
‘My first reaction was a violent negative. But the more I thought about this new theory, the more things it explained. My assumption of Konstanze’s innocence wasn’t logical. It was based on a number of emotional prejudices which I needn’t go into in detail.’
Tony snickered. I took the golden amulet from my pocket and handed it to him.
‘You weren’t exactly logical about Konstanze either,’ I reminded him. ‘And your emotional prejudices in her favour aren’t hard to understand. Take a look at this. I found it in the box with the arsenic. Then I remembered something you told me when we were discussing the witchcraft cult one time. I think it was the Burning Court affair, under Louis the Fourteenth, that set you off.’
‘Damn my big mouth all to hell and back,’ said Tony calmly. He handed the image to Blankenhagen, who was practically sprawled