'Britannia' four cylinder 18-24 hp ?
Correct! One point to you.
The Britannia Engineering Co Ltd built cars in Colchester Essex from about 1904 until around 1908, it is thought that the cars were not very successful despite a guarantee 'to replace in our Factory, Free of Charge, . . . any part manufactured and supplied by us, found within six months after delivery to be defective in material and workmanship"
An earlier company based at the same Britannia works called 'The Britannia Electric Carriage Syndicate Ltd'. built electric cars in the 1890s.
I can't find much information about either of these companies and details on the internet are quite sketchy and sometimes contradictory so if anyone has any information about Britannia cars in Colchester I would be very very grateful indeed to hear any further details. (The factory, or rather the site of the factory, is situated very close to where I live).