A £20,000 conservation grant from the ACE PRISM Fund will allow Exeter’s Royal Albert Memorial Museum (RAMM) to feature its 19th-century East India Company botanical drawings in an exhibition in 2016.

The set of 86 drawings was donated in 1927 from the collection of the Devon botanist, Reverend Richard Cresswell (1815-1882).

They are extremely rare and have high historical and scientific importance.

As far as is known, RAMM is the only non-national UK collection to hold original drawings from this group, the others being at Kew, the British Museum and the Natural History Museum.

The importance of the drawings came to light during RAMM’s 2012/3 Arts Council England funded collections review when Martyn Rix, a leading specialist in botanical art, was commissioned to survey its 400 botanical drawings.

The botanical drawings were commissioned from Indian artists, by the East India Company, probably under the supervision of the Calcutta Botanic Garden.

In the late 18th and early 19th century the Company set out to record the complete flora of India for the advancement of botanical science and for commercial exploitation – primarily food crops and medicines.

RAMM’s drawings relate to several printed publications of the era of William Roxburgh and Sir Joseph Banks, including Plants of the Coast of Coromandel, Hortus Bengalensis and Flora Indica. William Roxburgh was the superintendent of the Calcutta Botanic Garden from 1793 and is often called the father of Indian Botany.

Sir Joseph Banks was a leading patron of the natural sciences who is credited with establishing Kew as the world's leading botanical gardens.

The conservation of the drawings is particularly challenging because of the inherent fragility of the mediums; they are painted on paper with gouache and watercolour with pencil under-drawing and ink inscriptions.

As well as a fairly standard range of problems including surface soiling, creasing and tears, atmospheric pollution has caused the formation of acid in the paper, seen as discolouration and staining.

Pollutants have also caused lead-based colours to blacken, which has changed the appearance and colour balance of many of the drawings. Careful conservation work can reverse these changes and return the work to their original, stable colours.

The Preservation of Industrial and Scientific Material (PRISM) Fund is administered by Arts Council England and awards grants towards the costs of acquisition and conservation of items or collections which are important in the history and development of science, technology, industry, and related fields.