vast extent of ancient woods and intervening lawns, to which the eye sees no limit, and in whose walks it seems as if the whole population of London might lose itself.  North of Hyde Park, after passing a few streets, you reach the great square of Regent’s Park, where, as you stand at one boundary the other is almost undistinguishable in the dull London atmosphere.  North of this park rises Primrose Hill, a bare, grassy eminence, which I hear has been purchased for a public ground and will be planted with trees.  All round these immense inclosures, presses the densest population of the civilized world.  Within, such is their extent, is a fresh and pure atmosphere, and the odors of plants and flowers, and the twittering of innumerable birds more musical than those of our own woods, which build and rear their young here, and the hum of insects in the sunshine.  Without are close and crowded streets, swarming with foot-passengers, and choked with drays and carriages.

These parks have been called the lungs of London, and so important are they regarded to the public health and the happiness of the people, that I believe a proposal to dispense with some part of their extent, and cover it with streets and houses, would be regarded in much the same manner as a proposal to hang every tenth man in London.  They will probably remain public grounds as long as London has an existence.

The population of your city, increasing with such prodigious rapidity; your sultry summers, and the corrupt atmosphere generated in hot and crowded streets, make it a cause of regret that in laying out New York, no preparation was made, while it was yet practicable, for a range of parks and public gardens along the central part of the island or elsewhere, to remain perpetually for the refreshment and recreation of the citizens during the torrid heats of the warm season.  There are yet unoccupied lands on the island which might, I suppose, be procured for the purpose, and which, on account of their rocky and uneven surface, might be laid out into surpassingly beautiful pleasure-grounds; but while we are discussing the subject the advancing population of the city is sweeping over them and covering them from our reach.

If we go out of the parks into the streets we find the causes of a corrupt atmosphere much more carefully removed than with us.  The streets of London are always clean.  Every day, early in the morning, they are swept; and some of them, I believe, at other hours also, by a machine drawn by one of the powerful dray-horses of this country.  Whenever an unusually large and fine horse of this breed is produced in the country, he is sent to the London market, and remarkable animals they are, of a height and stature almost elephantine, large-limbed, slow-paced, shaggy-footed, sweeping the ground with their fetlocks, each huge foot armed with a shoe weighing from five to six pounds.  One of these strong creatures is harnessed to a street-cleaning machine, which consists of brushes turning over a cylinder and sweeping the dust of the streets into a kind of box.  Whether it be wet or dry dust, or mud, the work is thoroughly performed; it is all drawn into the receptacle provided for it, and the huge horse stalks backward and forward along the street until it is almost as clean as a drawing-room.