Consider the picnic on Box Hill in Emma. We modern readers can't help thinking about the servants preparing, carrying and setting out the meal, and then waiting respectfully at a distance while the ladies and gentlemen sat and ate it, and then cleaning up after the ladies and gentlemen when they were all finished with their nice al fresco repast. But none of that is mentioned in the novel, only a brief reference to servants and carriages at the end of the passage. To Austen, servants were a fact of life...
5. Mansfield Park includes repeated references to “pheasants,” game birds that were difficult to buy and that (like slaves, after the Mansfield ruling) couldn’t be legally recovered if they got away and so had to be carefully kept and carefully bred to maintain an adequate population. Jane barely mentions pheasants elsewhere in her writing.