𝐉𝐚𝐦𝐞𝐬 𝐌𝐚𝐫𝐬𝐡

JAMES MARSH

(2 September 1794 - 21 June 1846)

Introduction 

James Marsh was born on September 2, 1794, in Kent, England. He was a chemist. He worked as a labourer. 

He invented the marsh test which was used to detect arsenic. He was a skilled and Innova scientist. He also worked as an assistant to Michael Faraday at the nearby Royal Military Academy.

Contribution 

➔ Marsh carried out the standard test (MARSH TEST) by combining a suspected sample with hydrogen sulphide and hydrochloric acid. 

While he could detect arsenic as yellow arsenic trisulfide, when it came time to display it to the jury, the evidence had degraded, allowing the defendant to be acquitted due to reasonable doubt.

➔ Marsh got annoyed by this and invented a far better test. He mixed an arsenic-containing sample with sulphuric acid and arsenic-free zinc, producing arsine gas. 

➔ When the gas was burned, it dissolved into pure metallic arsenic, which left a silvery-black coating on a cold surface. 

➔ The test was so sensitive that it could identify as low as one-fifth of a milligram of arsenic. 

Awards

In 1836, the society of arts awarded Marsh its greatest honour, the large gold medal, declaring that the chemist had imparted an extraordinarily vast public benefit through his procedure.

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Written by

Lavanya Sri S

Volunteer 

Shivi Forensics