Published: 22/01/2022
Updated: 29/03/2023
On 23 March 1885, a group of more than 30 members and associates of the Sedgwick Club travelled 200 miles by train (steam of course!) from Cambridge to Portmadoc (Porthmadog) for a 10-day geological tour of the region.
The Sedgwick Club had been founded in 1880 in memory of Adam Sedgwick, one of the founders of British geology, and today it is the oldest student-run geology society in the world. From its inception, the club ran field excursions to places of interest across the breadth of the United Kingdom.
Geologists had been drawn to Portmadoc since the early 1800s. Although some were affiliated with educational institutions, many of those who came were ‘gentlemen scientists’ who could afford to study this emerging science as a hobby. In the local ‘Tremadoc Rocks’, enthusiasts and academics alike found physical evidence of long-extinct marine animals and geological time-scales that had previously been unimaginable.
David Homfray was one of the first to recognise the scientific value of the local geology. He was a Warwickshire lawyer whose uncle was the Manager of the Welsh Slate (Palmerston's) Quarry at Ffestiniog. His pioneering research and collaboration with Sedgwick put Portmadoc on the geological map.
To help me understand the the global significance of the Tremadoc Rocks, I asked two geologists to explain what was happening in the field of geology at that time:
"One of the great scientific enterprises of the 19th century was the creation of a geological timescale. At the beginning of the century, the “Father of British Geology”, William Smith, discovered that rocks could be classified in time order by their distinctive fossil content. Consequently, geologists such as Sedgwick were much engaged in placing the pages of the geological history of Earth in order and subdivided into periods with distinctive fossils, the periods carrying names associated with where these rocks were best exposed (e.g. “Jurassic”, named after the Jura Mountains). The numerical age in million years of the periods would not be possible until the invention of radiometric dating in the 20th century, but there was much personal and national pride at stake in the naming and ordering of the subdivisions."
Prof. Mike Simmons
"The Tremadoc rocks were deposited as clays on the floor of a sea, some 10s of metres deep, that covered what is now this area of Wales about 485 million years ago (a depositional region known as The Welsh Basin). We now refer to this period of time as the Tremadocian and it represents the earliest episode within the Ordovician Period of geological time. (These names and their meanings sound very local, but such is their historic importance that, in fact, they are internationally used.) When this story of ages and rock-types was first being unravelled in the first half of the 19th C, two geological heroes (Sedgwick, of Cambridge, and Murchison, of London) disagreed mightily about the transition between earlier rocks of Cambrian age, and the following rocks of Silurian age. Tremadoc rocks lay in that transition; Sedgwick wanted them to be Cambrian and Murchison wanted them to be Silurian. Only later in the century did the Ordovician Period get introduced (by Lapworth) to resolve the dilemma posed by the sediments that occupied the intermediate position. So, the Tremadocian became part of the Ordovician."
Dr. Tim Palmer
(You can see the Tremadocian layer in the diagram below, towards the bottom of the middle column.)
Penmorfa village was a particular hot spot of geological research. As well as the Tremodoc Rocks, it offered fossil-rich slate and shale known to geologists at the time as ‘Lingula Flags’, and was especially rich in trilobites — ancient crustacean-like creatures whose shed and discarded exoskeletons often became fossilised.
In 1843, J. E. Davis reported to the Geological Society of London seeing 'fucoids, appearing in great abundance in flagstones' near Penmorfa church.1 These are now understood to be a type of fossil burrow.
In 1865, Thomas Huxley, Darwin’s valuable ally, included nine fossil specimens from Penmorfa Church, and five more from Penmorfa village, in his Collection of Fossils for the Museum of Practical Geology, now within London's Natural History Museum. David Homfray also collected trilobites from the rocks around the church in the 1860s, which are now in the collection of the Sedgwick Museum in Cambridge. In fact, the Sedgwick Museum holds 167 fossil specimens from Penmorfa, and 32 of those were collected at, above, behind, or next to Penmorfa Church!
On the Sedgwick Club trip of 1885, the students, educators and other enthusiasts ventured out in all weathers to study and sketch the fossil-rich rocks, drew geological section diagrams, and record their discoveries.
This section drawing from the trip depicts the Tremadoc layer beneath Penmorfa village, and the Upper Lingula Flags right underneath Penmorfa Church.
There was also plenty of scope for fun; the group enjoyed visits to local heritage attractions and landmarks and along with their geological notes, the archive preserves sketches of chickens, a poster for a local play, and even some limericks!
Women would not be permitted to become members of the Sedgwick Club until 1896. Nevertheless, several women joined the trip to Portmadoc, and you can see four of them pictured in this wonderful group photograph ...
... as well as three in this relaxed snapshot from Penmorfa Village.
At St Beuno’s, Penmorfa, three of the women were pictured relaxing on the steps of the lychgate, while some local lads looked on.
They have been identified as:
Mrs Mary McKenny Hughes (1863-1917)
Mrs Hughes was the wife of Professor McKenny Hughes, 8th Woodwardian Professor of Geology, and she had a constant presence on expeditions during the 1890s, enabling other female students to attend. In 1888, she published ‘On the Mollusca of the Pleistocene Gravels in the Neighbourhood of Cambridge’.
Learn more about her.
Beatrice Katherine Taylor (1863-1934)
Beatrice graduated from Girton College, Cambridge in 1885, and became a teacher, with posts in Oxfordshire, Lancashire, and London. Indeed, she worked as a teacher right up to her death in 1934.
Ellen Stones (1853-1955)
The aptly named Ellen Stones graduated from Newnham College, Cambridge in 1885 and had a career as a teacher and educator in Berkshire, Carmarthenshire and London, before joining the Bishop Otter Training College in Chichester, a women-only teacher training college designed to increase the proportion of women teachers. She was involved in missionary work, forging alliances with educated women in Bombay, and also managed a ‘school for defective children’.
St Beuno’s lychgate was originally built in 1698 and reconstructed in the 19th century. Built of the local slate, it’s just one of many features in and around the church that showcase the geological richness of Penmorfa.
St Beuno's, Penmorfa is a church with hundreds of years of history, on the site of the 7th century cell of St Beuno, and it stands on rocks which contain the fossilised remains of ancient creatures from 480 million years ago.
Find Out More
Sandra Freshney, Archivist at the Sedgwick Museum, has published more information about the trail-blazing women who participated officially and unofficially in the Sedgwick Club: Being Seen & Heard – Women in the Sedgwick Museum Archives
All photographic images and the Penmorfa sketch are in the Archives of the Sedgwick Museum and are reproduced here with permission.
Read the full Obituary to David Homfray, 1893
With sincere thanks to Sandra Freshney, Archivist, Sedgwick Museum of Earth Sciences; Matt Riley, Sedgwick Museum Collections Assistant, Palaeontology; Prof. Mike Simmons; and geologist Dr. Tim Palmer.
