In May 1854 Pierce and Agar travelled to Folkestone to watch the process involved at that end of the line, particularly the location and security surrounding the keys. They spent so long, and were so obvious, in their surveillance that they came to the notice of the municipal and railway police. As a result, Pierce returned to London and left Agar to watch alone. As part of his intelligence gathering, Agar drank in the Rose Inn, a public house to the pier, where railway staff also drank. The pair concluded that one of the keys was carried by the superintendent of the Folkestone end of the line; the other was locked in a cabinet at the railway offices on Folkestone pier.