The question whether railway companies are entitled to support like other surface owners has been raised and fully argued in the House of Lords, and it has been decided that a railway company, under a statutory purchase of the surface land which does not include the subjacent minerals, cannot "claim the benefit of the right of an ordinary purchaser of the surface to subjacent and adjacent support, the statute having created a special law for such matters, by which alone the rights of the company and mine owners are regulated."

Special rights to excavate may also be acquired under Inclosure Acts.

Often rights of support in excess of the ordinary natural right for the support of surface are acquired for houses without any grant either express or implied. A right of support for a house may accrue from the mere fact that it has stood where it is for a long time (twenty years or more) and support has been enjoyed during that time.

This was decided by the House of Lords in that most remarkable case, Dalton v. Angus, reported in Appeal Cases, vol. vi. pages 740 to S52.

A perusal of the judgments and judicial opinions delivered in that case (which was very fully argued at different times before no less than eighteen judges, including the Lord Chancellor and four other Law Lords, three Lords Justices and the Lord Chief Justice and nine other Judges of the High Court), whose judgments and opinions fill altogether more than 180 pages of the Law Reports, should suffice to convince anybody of the excessive difficulty and complexity of the theory of the law relating to rights of support.

Since the final decision of that case there can no longer be any question that a right of support for buildings by land may be acquired by enjoyment for twenty years, although the theoretical foundations on which that right is built are still very obscure.

A few months after the final decision of the House of Lords in Angus v. Dalton it was decided by Hall, V.C., in Lemaistre v. Davis, that the principle of Angus v. Dalton applies also to lateral support of building by building. Twenty years of enjoyment creates a right to continued support. Before Angus v. Dalton was finally decided there had been some decisions exactly the other way.

It will be understood that all rights of support, whether they be simple natural rights or easement rights created by express or implied grant, or easements acquired by long enjoyment, are liable to be affected by private agreements or by Acts of Parliament.

Concerning rights of action and remedies for removal of support, a distinction must be made between the cases of neighbouring owners or occupiers who are prima facie acting within their rights in excavating their own land, and trespassers or wrong-doers who have no prima facie right to excavate.

These latter will ordinarily be liable for any damage caused by removal of support to a building, whether the owner had acquired an easement or not. The rightful owner or occupier is not liable for damage resulting from the exercise of his natural proprietary rights, unless he has exceeded his right by invading the rights of his neighbour. A wrong-doer, or a man acting without a bona fide claim of right derived from ownership, is liable any way for the damage he may do. The mere fact that a house is standing is enough to give a good title as against any one except the owner of neighbouring land or buildings or persons claiming under him.

In the early part of this chapter it has been pointed out that it is damage resulting from removal of support which gives a cause of action. Limitation begins to run from the date of damage, not from the date of removal of support, - indeed, it must in the nature of things be very difficult, if not impossible, for the person injured to know or ascertain in many cases what exactly is being done by neighbours which may weaken his support, and the possible effects and consequences cannot be clearly foreseen, so that when damage does actually occur, and only then, is it apparent that, for some reason or other, support was not sufficient.

The person complaining must be able to show the damage - to prove that it is due to removal of support by defendant - and to prove that his land and buildings were legally entitled to support at the time the damage was done. He must also be able to negative any counter explanation put forward to show that he has contributed to the result by his own acts, or the acts of others under his control, or that there have been some other or perhaps natural causes for what has happened.

Among the many possible causes which might account for damage might be bad building, structural defects, old age, increased weights introduced into the building, heavy or leaky roofs, bad drainage, and many other things which might have been done in and around the house by the occupier or others.

A man who has been apparently exercising his own proprietary rights on his own land in a reasonable manner for prima facie legitimate purposes, and in furtherance of what he may believe to be the best interests of his estate, cannot be easly held responsible for damage to buildings on a neighbouring estate.

The damage, the acts, the relation between them, the obligation to support, and the absence of other or contributing causes, may all come in issue, and the difficulties in the way of establishing a good case against a neighbour for damages for removal of support may often be very great, as indeed it is evident that they should be.

Everyone who wishes to build should as far as possible make adequate arrangements of every kind for the secure support of the buildings to be erected, and depend as little as possible upon the owners of neighbouring tenements.

From the fact that it is the damage consequent on acts done which gives a cause of action, it follows that each new damage gives a new cause of action, even when there have been no new acts to cause the extra damage.

It may readily be understood that when the foundations of a house have suffered injury by subsidence or fracture, or both, from want of sufficient support, the consequent damage to upper visible parts of the building may be progressive, either gradually or by fits and starts, and it may be difficult or impossible to foretell with any reasonable degree of certainty how far the damage may ultimately go. The liability ends only when the damage ends, but the damage must be traceable to the cause.