Thus is the census kept up and increased. The land, the towns and cities, are like hives in swarming time; a fertile queen indeed, and plenty of brood-comb! Were it not for the wildernesses of America, of Africa, and Australia, to which these swarms migrate, the people would suffocate and trample each other out. A Scotch or English city, compared with one of ours, is a kind of duplex or compound city; it has a double interior,--the interior of the closes and alleys, in which and out of which the people swarm like flies. Every country village has its closes, its streets between streets, where the humbler portion of the population is packed away. This back-door humanity streams forth to all parts of the world, and carries the national virtues with it. In walking through some of the older portions of Edinburgh, I was somehow reminded of colonies of cliff swallows I had seen at home, packed beneath the eaves of a farmer's barn, every inch of space occupied, the tenements crowding and lapping over each other, the interstices filled, every coign of vantage seized upon, the pendent beds and procreant cradles ranked one above another, and showing all manner of quaint and ingenious forms and adaptability to circumstances. In both London and Edinburgh there are streets above streets, or huge viaducts that carry one torrent of humanity above another torrent. They utilize the hills and depressions to make more surface room for their swarming myriads. One day, in my walk through the Trosachs in the Highlands, I came upon a couple of ant-hills that arrested my attention. They were a type of the country. They were not large, scarcely larger than a peck measure, but never before had I seen ant-hills so populous and so lively. They were living masses of ants, while the ground for yards about literally rustled with their numbers. I knew ant-hills at home, and had noted them carefully, hills that would fill a cart-box; but they were like empty tenements compared with these, a fort garrisoned with a company instead of an army corps. These hills stood in thin woods by the roadside. From each of them radiated five main highways, like the spokes of a wheel. These highways were clearly defined to the eye, the grass and leaves being slightly beaten down. Along each one of them there was a double line of ants,--one line going out for supplies and the other returning with booty,--worms, flies, insects, a constant stream of game going into the capitol. If the ants, with any given worm or bug, got stuck, those passing out would turn and lend a helping hand. The ground between the main highways was being threaded in all directions by individual ants, beating up and down for game. The same was true of the surface all about the terminus of the roads, several yards distant. If I stood a few moments in one place, the ants would begin to climb up my shoes and so up my legs. Stamping them off seemed only to alarm and enrage the whole