underhand work

underhand work

[′ən·dər‚hand ′wərk]
(mining engineering)
Picking or drilling downward.
References in classic literature ?
He said he admired you 'no end,' and that he wanted you to know it; but he didn't like being mixed up with that sort of underhand work, and he came to you and told tales.
Former Nissan worker John Hepple, who worked as a quality assurance team leader for seven years, told the tribunal: "Myself and colleagues were directed to carry out a lot of underhand work.
By the age of 42, O'Connor had risked and lost everything he had worked for - for the sake of pounds 11,000, the amount he made from his underhand work.