" NOT IN THE PRESCRIPTION" - No. 8797. Artist - P.D. NICKLIN.
I have come to believe that the signature is not P.D. Hicklin and is that of the artist Percy Bell Hickling (1876 – 1951) who was perhaps best known for his illustration of ‘Ladybird’ books. This artist can be found in the Census returns of both 1901 and 1911 in addition to the National Register of 1939.
I discovered this having tried unsuccessfully to find any artist / anyone who fitted the signature.