I recently read your 2009 article about the Tyco (Mantua) Trolleys of yesteryear. I still have a Mantua trolley that came with the cardboard tube and D cell batteries in 1955. The tube bit the dust a long time ago but the trolley has seen service on a number of layouts and still runs reasonably well. As long as the contacts and track are very clean. I have a camelback and a saddletank engine also of this vintage and they run well also.