40G AGRICULTURE [WASTE LANDS. good crops of wheat, beans, and clover, as well as Swedish turnips and mangolds ; but though a great quantity of manure was used, the crops fell off, and at present it is nearly all in grass. Tho portion which was bare sand was treated in the same way, except as to the first two crops of oats. It was green-cropped after it had been enclosed about two years. After the railway was made there was no means of silting the land. The tide was entirely kept out ; had it been admitted, this land would have been much more valu able and much higher we would then have had a better drainage and a richer sand. That portion which was grassed over at the time it was enclosed is still much the best. " When laud is reclaimed from the sea, the first thing to be looked to is a good outfall for the water, and, when it is possible, no doubt it is very desirable that the land should be silted up gradually. In our case this could not be done, as the reclamation of the land was a very secondary affair." In the district called Marshland, in Norfolk, extending between the Ouse and the Nen; in that called South Holland, in Lincolnshire, stretching between the Nen and the Welland ; northward of Spalding, and also north-east of Boston, there is a considerable tract of marine clay soil. In Marshland this is chiefly arable land, producing large crops of wheat and beans ; but in Lincolnshire it forms exceedingly fine grazing land. This tract lies within the old Roman embankment by which the district was first defended from the ocean. Outside this barrier are the proper marsh lands, which have been reclaimed in portions at successive periods, and are still intersected in all direc tions by ranges of banks. The extraordinary feature of this tract is, that the surface outside the Roman bank is 3 or 4 feet higher than that in the inside, and the level of each new enclosure is more elevated than the pre vious one. The land rises step by step as the coast is approached, so that the most recently reclaimed land is often 12 or even 18 feet higher than the lowest fen land in the interior, the drainage from which must nevertheless be conveyed through these more elevated marshes to the sea. Lands such as some of those which we have just been describing are often greatly improved, or rather may be said to be made, by means of a peculiar mode of irrigation called " warping." It is practicable only in the case of land lying below the level of high tide in muddy rivers. It is little more than a century since it was first practised in England, the first instance of it being near Howden, on the banks of the Humber. But although the practice is comparatively new in Britain, it has long been in use on the continent of Europe, particularly in Italy, and is thus described by Mr Cadell : " In the Val de Chiana, fields that are too low are raised and fertilised by the process called colmata, which is done in the following manner : The field is surrounded by an embankment to confine the water. The dike of the rivulet is broken down so as to admit the muddy water of the high floods. The Chiana itself is too powerful a body of water to be used for this purpose ; it is only the streams that flow into the Chiana that are thus used. This water is allowed to settle and deposit its mud upon the field. The water is then let off into the river at the lower end of the .field by a discharg ing course called scolo, and in French canal d ecoulement. The water-course which conducts the water from a river, either to a field for irrigation or to a mill, is called yora. In this manner a field will be raised 5J and sometimes 1 feet in ten years. If the dike is broken down to the bottom, the field may be raised to the same height in seven years; but then in this case gravel is also carried in along with the mud. In a field of 25 acres, which had been six years under the process of colmata, in which the dike was broken down to within 3 feet of the bottom, the process was seen to be so far advanced that only another year was requisite for its completion. The floods in this instance had been much charged with soil. The water which comes off cultivated land completes the process sooner than that which come off hill and woodland. Almost the whole of the Val di Chiana has been raised by the process of colmata" l Section 5. Blowing Sands. On many parts of our sea-coasts, and especially in the Hebrides, there occur extensive tracts of blowing sands, which are naturally not only sterile themselves, but a source of danger to better lands adjoining them, which in some instances have been quite ruined by the sand deposited upon them by the winds. This mischief is effectually pre vented by a process beautifully simple and useful, namely, planting the sand-banks with sea bent-grass (Arundo arenaria), the matting fibres and stems of which not only bind the sand, but clothe it with a herbage which is relished by cattle, and which, being able to resist the severest winter weather, furnishes a valuable winter forage in those bleak situations. The bent-grass can be propagated by seed, but in exposed situations it is found better to transplant it. This operation is performed betwixt October and March, as it succeeds best when the sand is moist and evaporation slow. CHAPTER XX. GENERAL OBSERVATIONS. According to the method proposed at the outset, we now offer a few observations on several topics connected with our subject. Section 1. Of the Tenure of Land. The extent of land in Great Britain occupied by its owners for agricultural purposes bears a very small pro portion to the whole area. The yeoman class is still numerous in several parts of England, but must have diminished greatly from that continuous amalgamation of small estates into large ones which has formed a marked feature in our social history during the present century. This change, although to be regretted on public grounds, has had a favourable influence on the cultivation of the soil, for it almost invariably happens that a larger produce is obtained from land when it is occupied by a tenant than when it is cultivated by its proprietor. As a matter of fact, the land of the country is now, with trifling exceptions, let out to professional farmers in quantities varying from the rood-allotment of the village labourer to the square miles of the Highland grazier. Farms of all sizes are usually to be found in any district, and most important it is that this should be the case ; but the extent of farms is chiefly determined by the amount of hired labour employed upon them, and the measure of personal superintendence on the part of the tenant which the kind of husbandry pursued upon them calls for. We accordingly find that in very fertile tracts, in the vicinity of towns, and in dairy districts, they seldom exceed 200 acres ; where the ordinary alternate husbandry is practised the average ranges from 300 to 400 ; in more elevated tracts, where a portion of natural sheep-walk is occupied along with arable land, it rises to 800 or 1000; while that of the sheep grazings of our hills and mountains is limited only by the capital of the tenant. About a century ago there occurred in various parts of Great Britain a similar amalgamation of small holdings into farms of the sizes which we have now re ferred to as is at present in progress in Ireland. This enlargement of farms, with the employment of increased capital in their cultivation, insures a more rapid reclama tion of waste lands, and general progress of agriculture up to a certain point, than would otherwise take place. But as every step in advance beyond this point implies an 1 Journey in Carniola, Italy, and France, by W. A Cadell, Esq.,
F.R.S.
