A double change has thus taken place. The transaction "with the copper and the balance," when intended to have for its office the transfer of property, is known by the new and special name of Mancipation. The ancient Nexum still designates the same ceremony, but only when it is employed for the special purpose of solemnising a contract. When two or three legal conceptions are spoken of as anciently blended in one, it is not intended to imply that some one of the included notions may not be older than the others, or, when those others have been formed, may not greatly predominate over and take precedence over them. The reason why one legal conception continues so long to cover several conceptions, and one technical phrase to do instead of several, is doubtless that practical changes are accomplished in the law of primitive societies long before men see occasion to notice or name them. Though I have said that Patriarchal Power was not at first distinguished according to the objects over which it was exercised, I feel sure that Power over Children was the root of the old conception of Power; and I cannot doubt that the earliest use of the Nexum, and the one primarily regarded by those who resorted to it, was to give proper solemnity to the alienation of property. It is likely that a very slight perversion of the Nexum from its original functions first gave rise to its employment in Contracts, and that the very slightness of the change long prevented its being appreciated or noticed. The old name remained because men had not become conscious that they wanted a new one; the old notion clung to the mind because nobody had seen reason to be at the pains of examining it. We have had the process clearly exemplified in the history of Testaments. A Will was at first a simple conveyance of property. It was only the enormous practical difference that gradually showed itself between this particular conveyance and all others which caused it to be regarded separately, and even as it was, centuries elapsed before the ameliorators of law cleared away the useless encumbrance of the nominal mancipation, and consented to care for nothing in the Will but the expressed intentions of the Testator. It is unfortunate that we cannot track the early history of Contracts with the same absolute confidence as the early history of Wills, but we are not quite without hints that contracts first showed themselves through the _nexum_ being put to a new use and afterwards obtained recognition as distinct transactions through the important practical consequences of the experiment. There is some, but not very violent, conjecture in the following delineation of the process. Let us conceive a sale for ready money as the normal type of the Nexum. The seller brought the property of which he intended to dispose--a slave, for example--the purchaser attended with the rough ingots of copper which served for money--and an indispensable