Jonathan Nash Hearder

Jonathan Nash Hearder (24 December 1809 – 16 July 1876) was a British electrical engineer, inventor, and educator. He is best known for his work in developing alternative experimental procedures for use by the blind and vision impaired, and for his early innovation in the field of induction coils.

Biography Hearder was born in Plymouth, Devon on 24 December 1809, the son of Jonathan Hearder (1775–1838, an umbrella maker and police constable) and Mary Hannah Hearder (née Parry). He was the eldest of four children, with one brother (George Parry Hearder) and two sisters (Mary Hannah Treleaven and Anne Eliza Page).

Hearder became interested in science at an early age, despite his father being "greatly averse to such pursuits". From the age of 17 Hearder gave lectures on topics of science at the Exeter Literary Institution and other local societies, He began a career as a schoolmaster, and was the first schoolmaster in Plymouth to include science as a subject in the school curriculum. It became Hearder's practice to wear green spectacles to conceal his damaged eyes.

Following the damage to his eyes, Hearder's school closed, and Hearder briefly turned to a secondary career in music.

In 1845 Hearder was appointed consulting electrician and galvanist to the South Devon and East Cornwall Hospital.

Hearder reportedly had an excellent memory, and held a passion for matters connected with local antiquity and history. He was an active member of the Devonshire Association and the Royal Polytechnic Society.

Hearder was the inventor in 1842 of a magnetometer, which he created with the object of ascertaining the rate of magnetic development in iron.