A visit to the salt store

An original account written in a nineteenth-century voice; a period simulation, not an archival document.

The warehouse keeper would not let me inspect the lower sacks. Rain had entered through a split in the roof during the night, and the bags beneath it had begun to dissolve into one another. He placed a handful from the upper shelf upon a slate for me to examine. Those crystals were dry, yet I could not judge the whole delivery by the portion he had chosen. My employer expected an account of every sack, not merely the finest handful in the building.

Explain two reasons why the narrator cannot assess the whole delivery from the keeper’s sample.