1st useless clue: it's British.
I suppose you may want a 2nd clue: active briefly (1921-1923) and that model have some French influences.
I'm getting nowhere. One more clue?
I have 2 models for this makers. The other has got a smaller Peter engine, 1200cc 9.5hp. They are from Chelsea. Short name.
That was a very generous clue! 
British Automotive Co. Ltd., Chelsea, London
This was a light car whose prototype was based on the Mathis, though production cars used Belgian-designed and British-built Peters engines in two sizes 1207cc 9.5hp and 1498cc 10.8hp. They were 4 cylinder side-valve units, and attempts to convert them to ohv were apparently unsuccessful. The gearbox was a 4-speed Meadows, and final drive was by shaft. Body styles included a 2 seater with dickey and a 4 seater. Probably no more than 20 were made.
If I'm allowed three more, I would like:
607
5380
8539
Thanks!
BAC is correcto but it's a matterof numbers now...
607:2 LITRE DROPHEAD COUPE, early 50s (1952?)
5380:MARLENE ROADSTER, 1988
8539:MODEL 15 RUNABOUT, 1909