A new vocabulary of sign language that will revolutionise the way science is taught to deaf children in schools throughout Britain has been developed by teachers and language specialists in Edinburgh.

Over the past year a glossary of more than 250 signs for scientific terms has been created that can be accessed over the internet by teachers, interpreters and pupils. Terms of daunting complexity – such as “photosynthesis”, “density” or “bacteria” — are explained by on-screen tutors who employ simple but descriptive gestures that suddenly create understanding.

Many pupils with perfect hearing find scientific terminology hard to comprehend, but for a deaf child the difficulties multiply. Nuances in the meaning of words such as “virus” make signed explanations difficult, and spelling out words letter-by-letter often leads to confusion.

“The scientific vocabulary for deaf children has developed simply because we needed it,” said Rachel O’Neill, a lecturer in deaf education at the University of Edinburgh. “People realised that there weren’t enough deaf teachers in schools and that finger spelling doesn’t work for complex subjects. You have to be able to understand the English first and then the concept and that can all be very difficult.”

Problems can be compounded because, with little access to the spoken word, deaf children often have poor reading skills, Ms O’Neill added.

By contrast, the simple gestures employed by the new system, unveiled yesterday at the University of Edinburgh, brought gasps of recognition when they were demonstrated to an audience of deaf children and their teachers.

The gestures, which are signed on screen, are supported by written explanations and fingerspellings. In some cases — such as “reaction” or “distillation” — additional information is supplied in demonstration videos.

The glossary is applicable for teaching in mathematics, biology, chemistry and physics, and it is hoped that more than 3,500 children who have been taught to use British Sign Language will benefit from the online glossary.

About 90,000 people use BSL. The British version is quite distinct from American Sign Language, but it has strong similarities with the sign languages used in Australia and New Zealand. Accessed over the internet, the glossary could be used by deaf teachers and children all over the world.

Gerry Hughes, the first deaf person to teach at a mainstream Scottish school, explained how the new biological signs worked.

Revealing the signed definition for “virus”, he made a clasping gesture, but kept his right hand open and wiggled his fingers as his hands came together.

“A virus is a single cell which can grow and mutate. We had had the image of a little devil of a cell that was aggressive and spread out, so that was the sign we made,” said Mr Hughes, who now teaches at St Vincent School for the Deaf in Glasgow.

The new definitions have been devised in a £25,000 project by a working party of teachers and academics at the Scottish Sensory Centre in Edinburgh. The scheme’s supporters hope that further grant aid from the Scottish government at Holyrood will enable the glossary to expand sufficiently to encompass standard grade level in the sciences.

This new classroom vocabulary represents a complete volte-face in official attitudes to the education of deaf people. In 1880 an International Congress on the Education of the Deaf in Milan agreed that oral education was better than manual learning, a decision that effectively outlawed sign language in classrooms all around the world for nearly a century. Only two deaf delegates were at the Milan conference, which closed the teaching profession to deaf people, and hampered their opportunities to work in other fields.

The ban was lifted in the 1970s and since then deaf people have very gradually been able to gain a wider variety of highly skilled jobs. In 1992, disability grants enabled deaf students in Britain to attend university and use the services of interpreters. More recently similar rights were extended to the workplace.

Audrey Cameron, who taught chemistry at Eyemouth High School in Berwickshire until she left recently to have a baby, is one of a new wave of highly qualified deaf people.

“It was only when I began to teach that I really began to understand the problems of many deaf children,” said Dr Cameron, who pursued academic research after graduation, but was not permitted to teach chemistry at university level, because of her disability.

“We don’t want our best people to suffer from being deaf. It depends on the individual but a profoundly deaf child will miss out — it is extremely hard for them to keep up.

“But I want deaf children to have that opportunity. We want more famous scientists,” she said.

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