These great streams of food, which we have thus so summarily described, flow into London so continuously and uninterruptedly, that comparatively few persons are aware of the magnitude and importance of the process thus daily going forward. Though gathered from an immense extent of country--embracing England, Scotland, Wales, and Ireland--the influx is so unintermitted that it is relied upon with as much certainty as if it only came from the counties immediately adjoining London. The express meat-train from Aberdeen arrives in town as punctually as the Clapham omnibus, and the express milk-train from Aylesbury is as regular in its delivery as the penny post. Indeed, London now depends so much upon railways for its subsistence, that it may be said to be fed by them from day to day, having never more than a few days' food in stock. And the supply is so regular and continuous, that the possibility of its being interrupted never for a moment occurs to any one. Yet, in these days of strikes among workmen, such a contingency is quite within the limits of possibility. Another contingency, arising in a state of war, is probably still more remote. But, were it possible for a war to occur between England and a combination of foreign powers possessed of stronger iron-clads than ours, and that they were able to ram our ships back into port and land an enemy of overpowering force on the Essex coast, it would be sufficient for them to occupy or cut the railways leading from the north, to starve London into submission in less than a fortnight. Besides supplying London with food, railways have also been instrumental in insuring the more regular and economical supply of fuel--a matter of almost as vital importance to the population in a climate such as that of England. So long as the market was supplied with coal brought by sea in sailing ships, fuel in winter often rose to a famine price, especially during long-continued easterly winds. But, now that railways are in full work, the price is almost as steady in winter as in summer, and the supply is more regular at all seasons. The following statement of the coals brought into London by sea and by railway, at decennial periods since 1827, as supplied by Mr. J. R. Scott, Registrar of the Coal Exchange, shows the effect of railways in increasing the supply of fuel, at the same time that they have lowered the price to the consumer: