Home Counties Meeting at Cobham
Saturday 22nd February 2025
This was the third Home Counties Meeting held in Cobham and organised by Joan Bingley. It was held again in the main hall of Church Gate House Centre adjacent to St Andrew’s Church in Cobham, Surrey. The hall has a kitchen where we could help ourselves to tea, coffee and biscuits. The day started with refreshments, followed by three talks, a break for lunch, and an afternoon of exhibits and gossip.
Church Gate House Centre
Talks
Martin Parnham “Galvanotaxis in ciliates”
The Paramecium that Martin has been working with are small, about 0.05 mm long, but they have about 4,000 cilia that they co-ordinate to enable them to move through water. They appear to move very quickly when viewed under a microscope, so Martin uses methyl cellulose to slow them down. He uses oat milk to provide tiny particles that reveal the currents produced by the cilia.
With direct current, he found that Paramecium move towards the cathode, and that they change direction if the polarity is reversed. With alternating current, they move in a direction perpendicular to the current.
Martin Parnham’s presentation
Martin has published a paper on the same subject: Initial observations of the effect of electric fields on ciliary motion in Paramecium and Stylonychia (Quekett Journal of Microscopy, 2024, 44, 461–470).
Quekett members can watch Martin’s videos of Paramecium.
You can see some of Martin’s equipment in the gossip notes.
Tim Fullick “Charles Darwin, microscopist”
During his life, Darwin used several microscopes on The Beagle and in his laboratory at Down House. He bought a ‘Cary-Gould’ box-mounted microscope when he was a medical student, and used it to study hornwrack, but he called it a “wretched microscope”. For his work on barnacles, he needed a better microscope and bought a Smith & Beck Large Achromatic Microscope. For his work on bladderwort, he later bought a Hartnack Noveau Petit Modèle because of its better objectives.
Tim Fullick’s presentation
You can see some of Tim’s microscopes in the gossip notes.
Ben Siggery “Palaeoecology for conservation: A case study of heathland management at Chobham Common”
Ben explained that he is part of a team that is examining soil cores from Chobham Common for changes in the abundance of diatom frustules, of remnants of plants and insects, and of spheroidal carbonaceous particles from the burning of fossil fuels. The cores are divided into 1 cm sections that are examined under microscopes, so that changes from the oldest (lowest) section to the present can be mapped. The changes can be related to factors including the industrial revolution and clean air legislation. Their findings will be used to devise a management plan for the Common, which could include reverting to a wetter state to help reduce the number of fires. The last record of a natterjack toad was about 100 years ago, when the pH was similar to the value now, so a re-introduction is being considered. Sadly there are no plans to re-introduce the diatoms that have disappeared.
Ben Siggery’s presentation
You can see the slides from Ben’s presentation here:
Click the arrows to move through the slides. Click the symbol at bottom right for a larger version.
Ben and his team have recently published an article on their work: Talking the same language: Co-production of a palaeoecological investigation to inform heathland management (Journal of Environmental Management, Volume 377, March 2025).
Lunch
For lunch, members could either bring their own or opt for fish and chips from a local shop, kindly ordered and collected by Joan Bingley.
Lunch
Gossip
As with any Quekett meeting, there was gossip before the talks and during lunch, as well as in the afternoon.
Mark Berry used two microscopes to examine squeezes from moss. One was a small trinocular Reichert compound microscope with Vickers phase-contrast condenser and objectives, and an eyepiece camera in the vertical tube feeding the Camera app on a Windows laptop.
Mark Berry
The other was a 50× digital microscope for which Mark had made a rigid stand. It had a grey horseshoe base with a jug handle, with a black rack and pinion fitted on top to provide some focusing. The camera was fitted in an old condenser mount that was attached to the black part. Mark used a Chinese mechanical stage for X and Y movements, and a small laboratory jack for raising and lowering the stage.
Mark Berry’s digital microscope
Joan Bingley brought an old Orion S240 stereomicroscope with illumination from an LED torch supported on a GorillaPod. Her specimens were three epiphytic bryophytes from a tree in Cobham, the liverwort Radula complanata, the acrocarpous moss Lewinskya affinis (formerly Orthotrichum affine) and the pleurocarpous moss Hypnum cupressiforme.
Joan Bingley’s exhibit
Joan also brought a book that we had not seen before, A Field Guide to Bryophytes by Dominic Price & Clive Bealey.
A Field Guide to Bryophytes
Tim Fullick brought three microscopes similar to those used by Charles Darwin. They were a Hartnack Noveau Petit Modèle, a Smith & Beck Large Achromatic Compound Microscope, and a ‘Cary-Gould’ Box-Mounted Microscope.
Tim Fullick (left), Phil Greaves, Martin Parnham and Bevil Templeton-Smith
Two of Tim Fullick’s microscopes
Smith & Beck accessories
‘Cary-Gould’ Box-Mounted Microscope
Phil Greaves brought a week-old hay infusion and two trinocular Leitz compound microscopes, a Laborlux III with Zernicke phase contrast and a Dialux II with a Heine condenser, each with a green filter. We were able to compare the appearance of ciliates and bacterial biofilms under the two versions of phase contrast.
Phil Greaves’ exhibit
Phil also showed a book, Free-Living Freshwater Protozoa: A Colour Guide by D. J. Patterson & S. Hedley
Albert and Winifred Greenfield
Pam Hamer used her Vickers polarising microscope to show slides that she had recently made of four cleaning products (Astonish Cream Cleaner, Astonish Stainless Steel Cleaner, Cif Cream and Pink Stuff) mounted in glass glue so that she could examine the abrasive particles. The colours produced under polarised light indicated that Cif contains calcite, Astonish Cream contains calcite and another crystalline substance, and Pink Stuff contains a silicate. Astonish Stainless Steel Cleaner contained very fine material with no clear particles.
Toni Fullick and Pam Hamer (right)
Albert Greenfield and Martin Parnham
Pam Hamer’s slides
Pam also brought some notes on identifying minerals using the colours produced by polarised light (including a Michel-Lévy colour chart), and examples of the Club’s free leaflets on things to look at with microscopes.
Michel-Lévy chart
Grenham Ireland has been looking at desmids from a pond in Dorset that he isolates in paraffin chambers in shallow depression slides. He brought several of the slides, and two microscopes so that we could observe the desmids. One microscope was a trinocular Zeiss Standard with a Panasonic DMC-GF6 mirrorless camera attached, the other was a trinocular stereomicroscope on a transmitted-light base with a Chinese inspection camera attached.
Grenham Ireland
Grenham Ireland and Graham Carey
Martin Parnham brought the trinocular Brunel compound microscope with infinity-corrected plan objectives that he uses to observe ciliates and to record them on the attached Canon EOS M50 mirrorless camera. He also brought examples of the equipment he has made for applying, modifying and measuring DC and AC current to water containing ciliates, and some of his Paramecium cultures.
Martin Parnham
Part of Martin Parnham’s apparatus
Desmond Squire (left), Martin Parnham and Phil Greaves
Acknowledgements
Our thanks to Joan Bingley for organising the event, providing the refreshments and collecting the fish and chips, and to all those who got out and put away the tables and chairs.
Report and photographs by Alan Wood