CHAPTER III - OF THE RIGHT OF ACCESSION TO WHAT UNITES OR INCORPORATES ITSELF TO THE THING
Art. 8. The right of ownership gives in general to the owner by right of accession, all that unites and incorporates itself to his property.
But this general rule is susceptible of several modifications, according as the thing to which the union is made, is moveable or immoveable, and, according to the various ways in which said union takes place.
SECTION I - OF THE RIGHT OF ACCESSION CONCERNING IMMOVEABLES
Art. 9. The property of the soil carries with it the property of what is over and under it.
The owner may make upon it, all the plantations and erect all the buildings which he thinks proper, save the exceptions established under the title of servitudes or services.
He may construct below the soil all manner of works, digging as deep as he deems convenient, and draw from the holes dug in the ground, all the benefits which may accrue, under such modifications as may result from the regulations of the police.
Art. 10. All the constructions, plantations, and works made on or within the soil, are supposed to be done by the owner, and at his expence, and to belong to him unless the contrary be proved.
Nevertheless a third person may, by possession alone, when the same is sufficient to operate prescription, acquire the property whether of a subterraneous piece of ground under the building of another, or of any other part of the building.
Art. 11. If the owner of the soil has made thereon constructions, plantations and works, with materials which did not belong to him, he has a right to keep the same on condition of reimbursing their value to the owner and paying damages if the case require it.
Art. 12. When plantations, constructions, and works have been made by a third person and out of said person's own materials, the owner of the soil has a right to keep them, or to compel this third person to take away or demolish the same.
If the owner requires the demolition of said works they shall be demolished at the expence of the person who erected them, without any indemnification, said person may even be sentenced to pay damages if the case require it, for the prejudice which the owner of the soil may have sustained.
If the owner keeps the works, he owes to the owner of the materials nothing but the reimbursement of their value and the price of the workmanship, without any regard to the greater or less value which the soil may have acquired thereby.
Nevertheless if the plantations, edifices, or works may have been done by a third person evicted but not sentenced to make restitution of the fruits, because said person possessed bona fide, the owner shall not have a right to demand the suppression of the said works, plantations or edifices, but he shall have his choice either to reimburse the value of the materials, and the price of workmanship, or to reimburse a sum equal to the enhanced value of the soil.
Art. 13. The sand bars and accretions, which form themselves successively and imperceptibly to any soil situated on the shore of a river or creek are called alluvions.
The alluvion belongs to the owner of the soil situated on the edge of the water, whether it be a river or a creek, and whether the same be navigable or not.
Art. 14. The same rule applies to derelictions formed by running water retiring imperceptibly from one of its shores and encroaching on the other, the owner of the land adjoining the uncovered shore has a right to the dereliction, nor can the owner of the opposite shore claim on this side, the land which he has there lost.
This right does not take place in case of derelictions of the sea.
Art. 15. If the river or creek whether navigable or not, carries away by a sudden irruption, a considerable tract of land from an adjoining field, which said tract of land is susceptible of being identified, by carrying the same on a field lower down, or on the opposite shore, the owner of the tract of land thus carried away may claim his property, provided he does it within the year, or even after the year has elapsed, if the person to whose land the soil thus carried away, has been united, has not yet taken possession of the same.
Art. 16. If a river or creek whether navigable or not, by opening itself a new bed, cuts off and embraces the field of any individual owner of the shore, and makes it an island, the owner shall keep the property of his field.
Art. 17. If a river or creek whether navigable or not, opens itself a new bed by leaving its former channel, the owners of the soil newly occupied, shall take by way of indemnification, the former bed of the river every one in proportion to the quantity of land he has lost.
They shall again take their former property, if the river or creek returns to its former channel.
Art. 18. Pigeons, bees and fish, which go from one pigeon house, hive or fish pond into another pigeon house, hive or fish pond, belong to the owner of those things, provided said pigeons, bees or fish have not been attracted thither by fraud or artifice.
SECTION II - OF THE RIGHT OF ACCESSION CONCERNING MOVEABLE THINGS
Art. 19. The right of accession, when it extends to two moveable things belonging to two different owners, rests altogether upon principles of natural equity.
The following rules shall direct the determination of the judge, in unforeseen cases, according to the peculiar circumstances of said cases.
Art. 20. When two things, belonging to different owners and which have been united in such a manner as to form a whole, are nevertheless of a nature to be separated, so that one may exist without the other, the whole belongs to the owner of the thing which forms the principal part, subject to his reimbursing to the other, the value of the thing which has been united to his own.
Art. 21. The part which is considered as principal is that to which the other has been united only for the use, ornament or completion of the other.
Thus the diamond is the principal part with reference to the gold in which it is set.
The coat itself with reference to the lace lining and embroidery.
Art. 22. Nevertheless equity requires that there should be some exception to the preceding rule, when the thing united is much more precious than the principal thing, and when it has been made use of unknown to the owner. In such case the owner may demand that the thing be separated and returned to him; even though there should thence result some injury to the thing to which it has been united.
Art. 23. If the two things united to form one whole, the one cannot be considered as the accession of the other, the most considerable in value, or in bulk, if the value be nearly equal, shall be considered as the principal.
Art. 24. If an artificer or any person whatever has employed materials which did not belong to him, in the making of a thing of a new kind, whether the materials may or not receive their former shape, the person who was the owner of the substance, has a right to claim the thing which was made out of it on reimbursing the price of the workmanship.
Art. 25. The rule established in the preceding article, does not apply when the workmanship is so important that is surpasses by far the value of the materials which have been employed. Industry then is considered as the principal part, and gives the workman a right to keep the thing which he has worked, on condition of reimbursing the price of the materials which were employed.
Art. 26. When a person has employed materials, part of which did, and part of which did not belong to him, in making a thing of a new kind, without either part of the materials being entirely destroyed, but in such a manner that they cannot be separated without inconvenience, the thing is common to both proprietors, to the one as to the materials which belonged to him, and to the other both as to the materials which belonged to him, and as to the price of the workmanship.
Art. 27. When a thing has been formed by a mixture of several materials belonging to different proprietors, each of which cannot be considered as the principal substance, the person unknown to whom the materials have been mixed may require the division of the same.
If the materials cannot be separated without inconvenience, their owners acquire in common the property of the thing, in proportion to the quantity, quality and value of the materials belonging to every one of them.
Art. 28. If the materials belonging to one of the proprietors, be far superior to the others both in quantity and value, in that case the proprietor of the most valuable materials, may claim the thing resulting from the mixture on reimbursing to the other the value of his materials.
Art. 29. When a thing belongs in common to the proprietors of the materials with which it has been formed, it must be sold at auction for the common benefit.
Art. 30. In all cases when the proprietor whose materials have been employed unknown to him, in making a thing of another kind, has a right to claim the property of that thing, he is at liberty to demand either that the materials be returned to him, in the same species, quantity, weight, measure and quality, or that their value be paid.
Art. 31. Against those who shall have employed materials belonging to others, unknown to them, may also be recovered damages according to circumstances and they are still liable to be prosecuted criminally, should the case require it.