South Kensington, UK. International Exhibition. Thallium makes its first public appearance. It had been discovered the previous year by William Crookes, through the observation of the bright green line in its spectrum. But Claude-Auguste Lamy also arrives in South Kensington with a 14-gram ingot of thallium, declaring that what Crookes had discovered was nothing more than an impure sulfide. Lamy had extracted the thallium from the residue lining the lead chambers of a sulfuric acid production plant.
