There are two reasons why I cannot grant to these plaintiffs the decree they seek, to set aside the whole of this trust deed. First. It was a voluntary conveyance on their part, and they seek to vacate it, not on the ground of a mistake as to matter of fact, but because they were ignorant what would be its legal effect and operation, and had made a mistake in a point of law. Now courts do not undertake to relieve parties from their acts and deeds fairly done on a full knowledge of the facts, though under a mistake of the law. (Lyon v. Richmond, 2 John. Ch. R. 51. Clark v. Dutcher, 9 Cowen, 649. Hunt v. Rousmanier, 8 Wheat. 174; S. C. 1 Peters, 1.) This is the general rule, that a mistake of this character is not a ground for reforming a deed founded on such mistake. But I do not mean to ássert that there are no exceptions to the rule, or that there may not be cases in which a court of equity will relieve against a plain mistake arising from ignorance of the law. The rule prevails in all cases of compromises of doubtful and perhaps in all cases of doubted rights; and especially in all cases of family arrangements; and is relaxed where there is a total ignorance of title, founded in the mistake of a plain and settled principle of law, and in cases of imposition, misrepresentation, undue influence, misplaced confidence, or surprise. And it may safely be affirmed, on the highest authority, as a well established doctrine, that a mere *283naked mistake of law, unattended with any such special circumstances as have been suggested, furnishes no ground for relief. (1 Story's Eq. Juris. §§ 137, 138.) The case under consideration appears to me clearly to come within the general rule, and not within the exception. There is no pretence of imposition, misrepresentation, undue influence, misplaced confidence, or surprise. These daughters, with the consent of their husbands, being seised of an absolute ownership of this property in severalty, saw fit to settle it upon themselves for life, and upon their children in fee after their death, so that it might be exempt from any control of, or responsibility for, any husbands which they then had or might afterwards have. So far they understood their rights, and seem to have had a due comprehension of what they desired; and so far no mistake of either law or fact is suggested. But in attempting to provide for the contingency of the daughters dying without children, it is alleged that they have made some limitations over which are void, which it is supposed they would not have made if they had well understood the law.
Allowing all this to be so, (and it is the strength of the case as made out for the plaintiffs,) I see in it nothing to bring it within the exceptions of the rule, but on the other hand, so far as two of the plaintiffs are concerned, a desire to take that which belonged originally to the wives, from a very proper settlement of it upon those wives and their children, and subject it to their own control and a liability to their debts. The claim does not commend itself to the favor of the court, and I cannot allow it, unless compelled to do so by some stern rule of law, which I have not yet found, nor been referred to.
Second. The other ground is that if these limitations over, after the death of the tenants for life, are void, as is claimed, it by no means follows that therefore the trust wholly falls to the ground and the plaintiffs become entitled to have it declared void.
I was a member of the court of errors when the case of Lorillard, the pioneer case under our new statute of uses and trusts, came before that court, and I always regarded with favor the *284idea of the chancellor of applying the doctrine of approximation to that will, and applying the nullification of the statute to those parts alone which absolutely required it. And I regretted to see the court of last resort use the instrument of destruction so widely as they did in that case, and in that of James’ will; and I accordingly rejoice now to perceive that as our courts have progressed in the task of interpreting that statute, they have returned to the sound views then put forth by the chancellor. It is now to be regarded as well settled, notwithstanding the earlier cases, that any legal trust is sufficient to sustain a devise or conveyance to a trustee, of an estate commensurate with such trust, without reference to the illegal trusts which the testator or grantor has attempted to create in the same estate. (Hawley v. James, 5 Paige, 458. Darling v. Rogers, 22 Wend. 483. Gott v. Cook, 7 Paige, 521. Irving v. De-kay, 9 Id. 527. Kane v. Gott, 24 Wend. 666.) And that in trusts of personal property, a suspension of the absolute ownership of a part, illegally, will not render void the disposition of the residue. (Van Vechten v. Van Veghten, 8 Paige, 128.) The statute is to be allowed to work out the destruction of the legal parts, only when they would of necessity uphold the illegal parts with them. The effect of the operation of this rule upon the case in hand is easily to be seen. It is to sustain this trust for at least the lives of two of the daughters, whatever may become of the remainder over after their deaths, and sustaining the deed thus far does not necessarily uphold any invalid limitations over.
The bill of complaint does not ask to have those limitations over declared void ; it seeks to set aside the whole trust deed ; to have it decreed that Susan Durand died intestate; that an account may be taken of what has come into the hands of the trustee; and that the residue, after due administration, be paid over to the plaintiffs. This cannot be done, under the view I have taken of this case. Thompson is holding under a trust, valid as yet, and it will be time enough to raise the other questions in the case when he shall claim to hold under one that may become invalid by some future occurrence. But it must *285not be inferred, because I have viewed the case as if the limitations over after the death of two life tenants were void, that I intend to hold that they are so. I have, it is true, examined that question, but I purposely abstain from deciding it; because my decision on that point is not necessary to the determination of this case.
There is only one other point which it is necessary to consider ; to wit, the objection that Mrs. Johnston’s trustees under her post nuptial settlement were not parties to the trust deed executed with Thompson. That marriage settlement was executed nine years before Mrs. Durand’s death, and of course conveyed no title to Mrs. Johnston’s trustees to the inheritance which she thus subsequently derived from her mother. Under the covenant contained in it, she and her husband might have been obliged to convey to them, in a proper manner; but until that was done, the title to, and ownership in, the property thus inherited, was in her and her husband, and it was not necessary to the validity of the trust deed to Thompson that the trustees under her marriage settlement should unite in executing it.
How far the execution of the deed by her and her husband can operate to give one set of trustees a preference over the other, is a question which does not arise here.