That was the regular way to do business on Arlington Street.

My father, in his three years' apprenticeship, had learned the tricks of many trades.

He knew when and how to "bluff." The legend of "Strictly Cash" was a protection against notoriously irresponsible customers; while none of the "good" customers, who had a record for paying regularly on Saturday, hesitated to enter the store with empty purses.
If my father knew the tricks of the trade, my mother could be counted on to throw all her talent and tact into the business.

Of course she had no English yet, but as she could perform the acts of weighing, measuring, and mental computation of fractions mechanically, she was able to give her whole attention to the dark mysteries of the language, as intercourse with her customers gave her opportunity.

In this she made such rapid progress that she soon lost all sense of disadvantage, and conducted herself behind the counter very much as if she were back in her old store in Polotzk.