in the early 1820s, two different papers are published on something that matches the description of naphthalene. both groups made it by distilling coal tar. in 1821 john kidd cited both reports, and condensed their results to accurately describe the properties of naphthalene, and how to make it. kidd named it naphthalene because "naphtha"  means any explosive hydrocarbon mixture. by 1826, michael faraday discovered the formula for it. emil erlenmeyer proposes that it is two fused benzene rings in 1866, and carl gräbe confirms this three years later.