Doorbell transformer with a vitreous ceramic base
The transformer as it would look when installed. The cover is actually dark brown, but someone has slapped several layers of emulsion paint over it.
The logo in the centre is a globe with an arrow through it, and the words 'Golden Arrow' over the front.
The transformer is completely open, and was probably wound by hand. The 240V supply is connected to the terminals at the left side. Note double 1A fuses and the rubber/cotton insulated wires.
The output terminals are on the right, and provide a selection of voltages (3V, 5V or 8V).
Back of the transformer, with the words 'BRITISH MAKE', 'VITREOUS' and '10472'.
The round logo is the word 'ENGLAND' with the letters 'JB' in the centre.
The metal part to the left-centre of the picture may have been a metal earth strap, which would have extended upwards across the base and through the small gap in the outer edge. Howewver this was missing when this item was found, so no way of knowing for sure.