Rehousing is overdue for the Sir Hans Sloane herbarium, dating from 1687. Its 70,000 specimens make up Britain's oldest scientific collection of dried plants and include the first preserved examples of sugar cane and of cacao, which gives us chocolate and cocoa. For years the collection was kept on shelves at the Natural History Museum, London.
Now, concerns about deterioration, a wish to make the collection more accessible and a sense of its uniqueness have prompted the museum to give it its own gallery. The 265 volumes are to be housed in a special room while the specimens and associated drawings are photographed. The pounds 150,000 room, largely financed by the Bernard Sunley charitable foundation, opens tomorrow evening. "This is the oldest extensive plant collection in Britain and of enormous value scientifically and historically," said Rob Huxley, head of botanical collections at the Natural History Museum. "It is a treasure from the age of exploration and discovery and it's absolutely right it should have a home of its own."
The herbarium was formed by Sloane (1660-1753), a doctor turned naturalist. On a visit to Jamaica from 1687-89 he collected 900 species of plants, many new to science, and brought them to England as pressed and dried specimens. He built on this by buying the entire collections of more than 100 other botanists over 60 years, many of them extensive.
Sloane was so badly bitten by the collecting bug that by the end of his life he had spread his net wider still, to embrace zoology, mineralogy, ethnography and art, and possessed one of the biggest single accumulations of objects put together by an individual.
His zoological collections comprised 9,000 shells, more than 4,000 insects, 1,500 fish, 1,200 birds, eggs and nests and more than 3,000 animal specimens, including the skeleton of an elephant.
He had thousands of fossils, rocks, minerals, metals and precious or semi-precious stones. He had a collection of 300 paintings, 32,000 medals and coins and a library of 50,000 bound volumes and a large collection of manuscripts and drawings.
He left the lot to the nation, on condition that it be properly housed and maintained. To oblige, the government in 1753 founded the British Museum: the Sloane collections were its nucleus.
The herbarium is one of the oldest pressed-plant collections in the world. Part of its great scientific value is that it contains many "type" specimens - the original example of the plant that was used when the species was named.
The sugar cane and cacao Sloane collected himself. He later made money by patenting the recipe for chocolate. Another "type" is the camellia, which a botanist brought from Japan.
Much of the herbarium's charm comes from the elegant drawings by the artist Everard Kickius, which accompany Sloane's specimens from Jamaica. "They've lasted for more than 300 years," said Dr Huxley. "Now we want them to last for another 600."