Possible Clues:

• An instrument for pounding
• What a nuisance with the French and with mortar!
• What a nuisance the French may work with mortar!
• Small club used with mortar
• That helps to do the groundwork with mortar
• This has the stamp of one that can work with mortar
• One might work this with mortar
• It grinds in a mortar
• Get ground with this, with the aid of mortar
• The piano gets bits of steel to work with mortar