Do you have the last page of the article, Bernard? P195 or whatever. It may mention the power supply.
My guess is that the power unit in the set is a battery box, perhaps for eight D batteries. There's no sign of a mains lead or a plug, as Kev says. The trackside building-style battery box presumably came later.
Not sure about 1957 but in the 1960s sets were sold without transformers because the latter were exempt from purchase tax (or were taxed a lower rate), and perhaps also because many people (like Floydfan) already had rail transformers.
Rob J
My guess is that the power unit in the set is a battery box, perhaps for eight D batteries. There's no sign of a mains lead or a plug, as Kev says. The trackside building-style battery box presumably came later.
Not sure about 1957 but in the 1960s sets were sold without transformers because the latter were exempt from purchase tax (or were taxed a lower rate), and perhaps also because many people (like Floydfan) already had rail transformers.
Rob J