It is also necessary to bear in mind the unspoken assumptions, the background, so to speak, existing in any writer's brain. It would make a great difference in a man's view of social conditions in 1825, say, if he was mentally contrasting them with the terrible scarcity and poverty that prevailed at the turn of the century, or if his recollections were mainly occupied with that bright period of prosperity enjoyed by the weavers some years earlier, a prosperity brief indeed, but lasting long enough to make a profound impression on the minds of those who shared in or witnessed it. Another consideration which is of use in clearing up the chaos of historical evidence on these questions, is the immense variety in conditions from one factory to another. This is the case even at the present day, when the Factory Act requires a certain minimum of decency and comfort. The factory inspectors record the extraordinary difference still existing in these respects, and, as a personal experience, the present writer well remembers the extreme contrast between two match factories visited some years ago at a very short interval; the one crowded, gloomy, with weary, exhausted, slatternly-looking girls doing perilous work in a foul atmosphere; the other with ample space, light, and ventilation, the workers cleanly dressed, and supplied with the best appliances known to make the work safe and harmless. Such an experience is some guide in helping the modern student to comprehend more or less why Fielden wrote of _The Curse of the Factory System_, while Ure could maintain: "The fine spinning mills at Manchester ... in the beauty, delicacy and ingenuity of the machines have no parallel among the works of man nor _in the orderly arrangement_, and the value of the products."