The deed of the Commonwealth, of Massachusetts under which the demandant claims, bears date Oct. 3d, 1797, and the controversy between the parties is, what is the true place of the east line of the tract conveyed, which now forms the town of Dutton. The defendants contend that a certain hemlock tree is the true corner bound of the tract. The plaintiff contends that a certain hard-wood tree is the true bound. These trees are between 130 and 160 rods distant from each other. The defendants also hold under the Commonwealth by a deed dated Sept. 21st, 1825, a tract of land adjoining the before named tract conveyed to Jackson. In order to shew that the plaintiff’s action is not maintainable for the land in dispute and that the line which he *428contends for is not the true one, the deed of the Commonwealth to Treat, of June 9, 1806 — the contract of May, 1819, and the deed of 1826 from Paries and Lowder to Johnson, were offered, objected to, and admitted. ■ The defendants do not claim under either of those deeds, or the said contract. The question is, whether they were legally admitted ; or, in other words, were the two former competent evidence, as the declarations of the Commonwealth, by its agents, or the latter as the declarations of Parles and Lowder ? — being declarations made many years after the date of the deed of the Commonwealth to Jackson, under which the demandant holds. It is an undisputed principle that no declarations of a grantor can be admitted to impair the title which he had previously conveyed, or limit the extent of his grant, or locate the boundaries; for all these things are in derogation of the title and rights he has conveyed. The above documents would not have been offered in evidence, with any other view than to limit the claim of the demandant and defeat the present action. What right could a grantor have thus to interpose ? —■ But it is said that the question in issue is, where is the true divisional line ? Be it so. The parties consider it a question of interest and importance to them, and why should the grantor by his declarations or opinions be permitted to influence the decision of the question ? It is said that the making of the deed to Treat, and the contract with Burgess and Sears was an act, shewing or tending to shew the true position of the divisional line. If it was such, and agreed to by the demandant or those under whom he claims, it would be so; and so would any parol agreement of the parties, had the admitted documents, which were objected to, never existed. We have no proof before us that ever such assent was given, or such documents kown to the demandant. The proof admitted .to shew that the demandant had acknowledged that the true line was the one contended for by the defendant, was properly admitted ; but that is a very different species of proof from that which was objected to. Beyond this, there.seems to be a stronger objection to the admission of the deed from Parks and Lowder to Peter Johnson. — They are not the persons under whom the demandant claims. What circumstance can give any right to the admission of the declarations or opinions of Parks and Lowder, as evidence in this *429cause against tbe demandant, more than the declarations or deeds of any other persons? We cannot perceive any principle on which such declarations could be admitted. It is stated that the proof objected to was admitted to show that the Commmonwealth, by their agents and those claiming under them, had claimed and exercised ownership over the land in controversy: and what if they had ? It could not affect the title previously granted, or the limits or location of the grant; nor is it any open act of ownership over the land, w hich in the present case could have any effect; and as to the claims of Parks and Powder in 1826, surely the demand-ant is not to be affected by them. The verdict must be set aside and a new trial granted.