I wondered, as I re-read the previous post, what my late mentor and friend John Carter would have called the diatom I was writing about. When I first started looking seriously at diatoms in the early 1990s, there was no-one in my laboratory in Durham with any experience from whom I could learn, and Brian Whitton suggested I went up to visit John at his home near Hawick, in the Scottish Borders. I rung to arrange a date and, a couple of weeks later, made the two hour drive up through Northumberland and across the border to his house in the small village of Denholm. Stepping into John’s study was like stepping back in time fifty years: it was dark and dusty, with piles of books and file boxes lining the walls and stacked on tables, along with boxes of microscope slides. In the fireplace there was some of the equipment that he used to digest his diatom samples – apparatus that really belonged in a laboratory fume cupboard. And, on a narrow desk against one wall, an old brass microscope equipped with a tilting mirror rather than its own light source.
John Carter in his study at Denholm, in Scotland. An uncredited photograph from his obituary in Diatom Research.
We spent the day in this study, John peering down his microscope and calling out the names of the diatoms he saw along with a commentary on the diatomists he had known (Hustedt, I remember him telling me, was a member of the Nazi party, which made it difficult for him to re-integrate with the scientific community after the war). I perched on a chair beside him taking notes and occasionally squinting down the microscope to see for myself what he was describing. I often, too, got a pithy assessment of the state of the slides that I had brought with me. After a couple of hours of this, we would be summoned by his wife into the dining room for a hearty casserole, and while we ate they would quiz me about my children and talk about their years in the Borders.
Later, back in Durham, I would go back through the slides and try to reconcile my notes with what I could see under the laboratory’s much more modern microscope, ever marvelling at just how much detail John had been able to see with his old equipment. It was a steep learning curve but, after half a dozen visits to John, it all began to make sense, and I gradually gained the confidence I needed to identify diatoms on my own. Not long after that we had a telephone call in the laboratory to say that John Carter had died. I felt that a door onto an older, more civilised, way of doing science had closed.