Upon what other system can it have been grown than the _open-field system_? The universal prevalence of this system makes it almost certain that the fields found by Cæsar waving with ripening corn were _open_ fields. The open-field system was hardly first introduced by the Saxons, because we find it also in Wales and Scotland. It was hardly introduced by the Romans, because its division lines and measurements [p250] are evidently not those of the Roman _agrimensores_. The methods of these latter are well known from their own writings. Their rules were clear and definite, and wherever they went they either _adopted the previous divisions of the land_, or set to work on _their own system of straight lines and rectangular divisions_. We may thus guess what an open field would have been if laid out, _de novo_, by the Roman _agrimensores_; and conclude that the irregular network or spider's web of furlongs and strips in the actual open fields of England with which we have become familiar is as great a contrast as could well be imagined to what the open field would have been if laid out directly under Roman rules. We happen to know also, from passages which we shall have occasion to quote hereafter, that the Roman _agrimensores_ did find in other provinces--we have no direct evidence for Britain--an open-field system, with its irregular boundaries, its joint occupation, its holdings of scattered pieces, and its common rights of way and of pasture, existing in many districts--_in multis regionibus_--where the red tape rules of their craft had not been consulted, and the land was not occupied by regularly settled Roman colonies.[338] The open-field system in some form or other we may understand, then, to have preceded in Britain even the Roman occupation. And perhaps we may go one step further. If the practice of ploughing marl into the ground mentioned by Pliny was an early and local peculiarity of Britain and of Gaul, as it seems to have been from his description, then clearly [p251] it indicates a more advanced stage of the system than the early Welsh co-aration of portions of the waste. The marling of land implies a settled arable farming of the same land year after year, and not a ploughing up of new ground each year. It does not follow that there was yet a regular rotation of crops in three courses, and so the fully organised three-field system; but evidently there were permanent arable fields devoted to the growth of corn, and separate from the grass land and waste, before Roman improvements were made upon British agriculture. «Was the system manorial?»