Bernard Knight - Where Death Delights

‘On call twenty-four hours a day for a hundred-and-fifty quid!’ exclaimed Sian. ‘I should join a trade union if I were you, Doc! Chaps sweeping factory floors get more than that for a forty-hour week!’

Her socialist crusading spirit was aroused, but Richard calmed her down by pointing out that he doubted that he would be called on very often, as he did not have a specific area to cover, but was only going to act as a back-up for other pathologists, as he had done in the Gloucester shooting.

‘I don’t know who fixed this up,’ he said ruminatively. ‘Brian Meredith and his brother have friends at court, so to speak, but so does Arnold Millichamp. And, of course, the Gloucester CID may have passed the word up to their Chief Constable.’

Whoever it was, the welcome title all helped towards consoli-dating their venture’s position in the forensic community. Several weeks passed and he had no other calls on his new status, but Moira sensibly suggested that as the summer holiday season had finished, other pathologists were no longer in need of a locum.

‘We’ll have to wait for one to break a leg or come down with malaria or something!’ suggested Sian, facetiously.

A few days later, the dangerous waters of the Severn estuary provided another body for Richard Pryor to examine at the Chepstow mortuary. Though badly decomposed, the police found a Seaman’s Identity Card in the remnants of the clothing and the index number was traced through the Central Register of Seamen. The victim was identified as a deckhand who went missing off Lundy Island two months earlier from a tanker taking crude oil for the Llandarcy BP refinery at Swansea. Richard found the body too far gone for a diagnosis of drowning and thought it a good opportunity to try out the controversial diatom test once again.

In their laboratory next morning, Angela once more showed Sian each step of the process. Small pieces of the tissues were taken, with precautions to avoid surface contamination with body fluids.

‘That’s to eliminate false results from getting diatoms other than via the bloodstream,’ she explained. ‘It doesn’t matter about the lung, because that’s going to be contaminated anyway, down the windpipe.’

Sian watched as the tissues from each organ were heated in small beakers of concentrated nitric acid in the fume cupboard, a dangerous operation if not done with great care, as the brown fumes from the highly corrosive liquid spiralled up into the exhaust outlet.

It took a long time for the digestion to get rid of all the organic material, but when the extracts had cooled, Angela put a portion of each into conical-bottomed centrifuge tubes and diluted them with distilled water.

‘Couldn’t you use tap water?’ asked Sian, always cost-conscious, but Angela shook her head.

‘Not safe to do that,’ she advised. ‘It often contains diatoms that grow inside the pipes.’

The digests were centrifuged to throw what was left of the solids down to the bottom of the tubes, then she repeated this twice more to dilute the acid to harmless proportions.

‘Now let’s have a look at those,’ she said, taking the tubes over to the microscope.

Putting a drop of the final sludge on to a glass slide and dropping a coverslip on to it, she peered through the eyepieces for a few moments, twiddling the stage controls to move the slides around under the high-power lenses.

Then she leaned back to let Sian’s glossy head take her place. ‘Plenty in the lung! Have a squint at those. Good old Bristol Channel diatoms!’

When Sian had satisfied herself, Angela went through the extracts from brain, liver, bone marrow and kidney.

She was glued to the microscope much longer this time, but eventually got up and declared herself satisfied.

‘Thought we were going to draw a blank, but the marrow has hit the jackpot,’ she said. ‘You need to find a reasonable number of diatoms, not just one or two – then hope the chap hadn’t been eating cockles or oysters the night before!’

Her technician seemed very taken by the technique and wanted to practice for herself.

‘I’ll have a go at the next body from the water myself,’ she promised. Angela, impressed by her keenness, had a suggestion.

‘We kept some tissues from the Gower case. Why don’t you use those, as Richard was convinced she was drowned, so it should be a good positive.’

Full of enthusiasm and without any other pressing work for the moment, Sian looked out the labelled pots and started on the digestions. Angela kept a motherly eye on her from a distance, but let her get on with the procedures herself. By the afternoon, the acid digestion was completed and Sian happily made up the slides from the various tissues.

She spent a long time staring at them down the microscope, while Angela was busy with a paternity test on another bench.

‘Any joy, Sian?’ called the biologist eventually.

‘Plenty in the lungs, but of course, you said that’s of no use in proving drowning,’ she replied, sounding rather disappointed.

‘Are there none in the other organs, then?’

‘Yes, I’ve only found half a dozen in the kidney and another five in the marrow. Is that enough?’

Angela rose and came across the room.

‘Let’s have a look. Lung first, eh?’

Sian gave up her seat and stood alongside, while Angela peered down the instrument, then slid the other organ slides into place under the lenses. This seemed to go on for a long time and the technician became restless.

‘Did I do it properly?’ she asked anxiously.

Angela made no direct reply but asked her to hand down a book from a nearby shelf.

‘The thin green one, on the end,’ she said in a worried tone. She riffled through the pages and Sian saw dozens of photographs and drawings of diatoms, some boat-shaped, some circular, others like needles.

‘Give me that lung slide we made this morning, please. The one from the oil tanker death.’

Still with no explanation, Angela changed the specimens on the microscope stage, then changed them back again.

When she looked up at her technician, her face was serious.

‘Sian, can you give Richard a call, please? I think we’ve got a problem!’

‘But that’s bloody impossible!’ he exclaimed. ‘Linda’s body was hauled out of the sea by the coastguards, so we know she was in there!’

Angela shook her head stubbornly.

‘I’m not denying that she had been in the sea, there are plenty of marine diatoms in her lungs. But she didn’t die in sea water. It was fresh!’

Richard stared down the microscope, though he was none the wiser until Angela pointed out various illustrations in the atlas of diatoms that was still open on the bench.

‘The ones in the kidney and marrow are all freshwater species, no marine ones at all. There are stacks of them in the lungs as well, but of course they’re mixed with marine diatoms, as she had been submerged later in the sea.’

Pryor jumped from the stool and paced back and forth.

‘There’s no possibility of some mistake?’ he demanded. ‘Could the samples have been mixed up?’

Angela was unruffled. She pointed to the bench top.

‘There are the pots in front of you! You were the one who brought them back and it’s your writing on the labels, as well as the signature of the DI who was there.’

Sian, who had been standing wide-eyed listening to this, decided to join in.

‘I was the one who did the digestion, Doctor. I’ll do it all over again, just to make sure.’

Moira came in with some forms to sign and immediately sensed that something was going on.

‘What’s happening?’ she asked. ‘Am I interrupting something?’

‘These two ladies have thrown a great big spanner in the works!’ said Richard. ‘I suppose we should have looked for these blasted diatoms straight after I did the PM, but it just didn’t seen necessary, it was so obvious that she had drowned.’