Possible Kirby inks per Nick Caputo based on an examination at his blog: http://nick-caputo.blogspot.com/2011/09/kirby-inking-kirby.html. Previous indexer credited Dick Ayers.
The Eel next appears in issue #117 (February 1964). The Eel, with his blueish-purple costume and oily-slick coating may have inspired the villain on the 1967 Spider-Man cartoon, "The Slippery Doctor Von Schlick". Charles Lawson, an atomic scientist, may have been related to Walter Lawson, an expert in guided missiles, who died in Marvel Super-Heroes (Marvel, 1967 series) #13 (March 1968). The plot about a miniature atomic pile which eventually explodes is similar to the Mike Hammer film, "Kiss Me Deadly" (1955).