unknown maker mark and hall mark

[phil_pp]

i have a teapot with stamp mark that are LEFT TO RIGHT READ LIKE THIS WM IN A OVAL , A CROWN IN A SHEILD THE A STANDARD LETTER S IN A CIRCLE THEN 2 CHARACTER LETTERS UNKNOWN LETTERS AND THEN THE NUMBER 1496
IN WOULD LIKE TO KNOW WHO THE MAKER IS AND WHEN IT WAS
MADE IF POSSIBLE AND WHAT IT MADE OFF
ANY HELP YOU CAN GIVE ME WOULD HELP I HAVE LOOK ON THE NET AND IN JACKONS HALL MARKS THE ONLY WM I FOUND WAS FOR WILLIAM MOULSON BUT NOT ALL THE MARKS FIT WITH IT FOR THAT YEAR
http://sv1.letmehost.com/sv1/7/IMG_2472.JPG
[img]http://sv1.letmehost.com/sv1/7/8f_12_sb[1].jpg[/img]

[Neruda]

Your teapot is silverplate - the last two stamps read E P for electroplate.
Although I don't know W M, the manufacturer, the crown and letter S suggest Sheffield, and a common practice of creating a certain ambiguity with Sheffield assayed sterling silver. This practice was stopped c.1895