PROTEUS
"On the top of the Howth tram alone crying to the rain: naked women! naked women! What about that, eh?" (U3.133)
A tram line connecting Sutton Station to Howth opened in 1901. It was 5 five mile long, and was operated by the Great Northern Railway. On this PC, notice the tram's open upper level, where Stephen would likely be standing in the rain.