Under the microscope
Many of the organisms on Earth are so small that you need a microscope to appreciate them individually. However, some that are individually small have contributed significantly to the Earth’s structure.
Corals live in colonies that build a hard protective structure around themselves. Reefs around tropical islands are almost entirely built by corals.
Similarly, the ancient remains of foraminifera shells formed deep deposits on the sea bed. These deposits are recognised today as beds of chalk. The chalk cliffs, with bands of flint, that can be seen near Beer in South Devon are largely made from these tiny animal shells.
Sponges and diatoms
Sponges and diatoms are extremely abundant creatures in the open oceans. They use a glass-like substance to encase themselves or to form the framework for a colony. Millions of years after their deaths their remains can form flint rocks.
Radiolarians also form part of the marine plankton. When they die their skeletons sink to the bottom and form ‘radiolarian ooze’.
Preserving these tiny organisms
Individual radiolarians, diatoms and others are so tiny that scientists and collectors have preserved them on glass microscope slides. Sometimes these slides are just simple spreads of organisms. Others are works of art where the organisms have been arranged in intricate and beautiful patterns.
One of RAMM’s hidden treasures is the collection of Victorian microscope slides. The collection contains as many as 7,000 individual slides and is a unique insight into a strange and colourful world that had previously been invisible to the naked eye. The shapes, patterns and textures shown on the slides reveal the incredible variety of subjects that were studied by Victorian naturalists including Percy Sladen and W. B. Carpenter.
Percy Sladen was fascinated by the natural world from an early age, but after visiting a marine research station, he became particularly interested in starfish, sea urchins and sea lilies; the echinoderms. Preparations of these creatures formed the basis of his collection including very small whole animals but also sections of their limbs and spines.
He acquired the slide collections of Dr. W. B. Carpenter and that of Carpenter’s son, P. H. Carpenter. W. B. Carpenter had trained as a medical doctor and as part of his training he studied a wide variety of life forms. He prepared microscope slides of their organs and tissues in order to prepare himself for a better understanding of the functioning of the human body.
Specimens included animal hair, blood (sometimes the maker’s own) cross-sections of bone, feathers and the iridescent wings of moths and butterflies. Insects were a particular favourite. They were often dissected to show details such as eyes, legs, jaws, wings, antennae, mouthparts and even stings. Some of the most spectacular forms of life prepared on slides are single-celled, plant-like creatures called diatoms and foraminifera.
These microscopic creatures, called radiolarians, have an intricate mineral skeleton and are found in marine plankton