Proton from different gases had different values of charge-to-mass ratio (e/m), they could not be identified with a single particle, unlike the negative electrons discovered by J. J. Thomson. Wilhelm Wien in 1898 identified the hydrogen ion as particle with highest charge-to-mass ratio in ionized gases. Following the discovery of the atomic nucleus by Ernest Rutherford in 1911, Antonius van den Broek proposed that the place of each element in the periodic table (its atomic number) is equal to its nuclear charge. This was confirmed experimentally by Henry Moseley in 1913 using X-ray spectra. In 1917 (in experiments reported in 1919),
Cassidy (given name) Cassidy (given name) Cassidy is a given name derived from an Irish surname and ultimately from the Gaelic given name "Caiside", meaning "clever" or "curly-haired." The name "Caiside" comes from the Gaelic word element "cas", according to "Behindthename.com" Cassidy was the 244th most popular name for girls born in the United States in 2009. It was most popular in 1999, when it was the 99th most popular name for American girls. It first appeared among the 1,000 most popular names for American girls in 1981. Kassidy, an alternate spelling, was ranked as the 443rd most popular name for girls in