Is this the early signature of William Marples senior?

[toolsntat]

Almost invisible to the naked eye and unbeknown to me when I bought this little 6" hand engraved steel square is this signature on the blade.
There may be something between the Marples and Sheffield but its too rusted to read

Andy

 

[Bod]

If its engraved, rub with school chalk, then wipe off with a dry cloth. the white chalk should stay in the engraving, revealing all!
If it works, photos please.

Bod