Fleet Ditch became such a nuisance that it was partly filled up by act of parliament soon after these lines were written. The Londoners had then their reservoirs of filth, called laystalls, in various parts near the river; and the pestilent accumulations spread disease all over the city. The system of sewers was begun in 1756, and from that time to the present several hundreds of miles of sewers have been constructed. But, alas, the Thames itself is now "the king of dykes," and the metropolis, healthy as it is, will never attain the sanitary state of which it is capable till the whole system of the outfall of the sewers is changed. The necessary work would involve the expenditure of millions. But the millions must be spent. In the mean time it is satisfactory to know that in towns of smaller population, where the evil is far less vast, and the natural difficulties of removal greatly less, the work of purification is going on rapidly. Public opinion has gone so strongly in the direction of a thorough reformation, that the duty can no longer be neglected. Every thousand pounds of public capital so expended is an addition to one of the best accumulations of national wealth. CHAPTER XVI. Early intercourse with foreign nations--Progress of the cotton manufacture--Hand-spinning--Arkwright--Crompton-- Power-loom--Cartwright--Especial benefits of machinery in this manufacture. There was a time when the people of England were very inferior to those of the Low Countries, of France, and of Germany, in various productions of manufacturing industry. We first gave an impulse to our woollen trade, which for several centuries was the great staple of the country; by procuring foreign workmen to teach our people their craft. Before that period the nations on the Continent had a proverb against us. They said, "the stranger buys of the Englishman the skin of the fox for a groat, and sells him the tail again for a shilling." The proverb meant that we had not skill to convert the raw material into an article of use, and that we paid a large price for the labour and ingenuity which made our native material available to ourselves. But still our intercourse, such as it was then, with "the stranger" was better than no intercourse. We gave the rough and stinking fox's skin for a groat, and we got the nicely dressed tippet for a shilling. The next best thing to dressing the skin ourselves was to pay other people for dressing it. Without foreign communication we should not have got that article of clothing at all.