Wells, J.

The plaintiff shows no right to hold the money deposited with the defendant by David Knowles. It was not money that belonged to her originally, as was the case in Farrelly v. Ladd, 10 Allen, 127, and Hunnewell v. Lane, 11 Met. 163, relied upon by the plaintiff’s counsel. The money belonged to David Knowles in his own right. He was not in fact trustee for Eliza Knowles, otherwise than by the form of the deposit. He was under no previous obligation to pay the money to her, or to hold it for her benefit. The voucher for the deposit, without the production of which, according to the conditions under which it was made, it could not be withdrawn, was never delivered to her, but retained exclusively in his own hands. Wall v. Provident Institution for Savings, 3 Allen, 96. The whole transaction was his own voluntary act, to which she was in no way a party or privy. There was no declaration made to *231her, or to be communicated to her, of any intention that the money should be hers. Even if the form of the deposit is to be taken as conclusive proof of the existence of such an intention in his mind, the execution of that intent was not so far complete as to operate to pass the title. Knowledge of the gift, on the part of the donee, at the time it is made, is not essential, it is true, in order that it may take effect. If the act of transfer be complete on the part of the donor, subsequent acceptance by the donee before revocation will be sufficient. But there must be some act of delivery out of the possession of the donor, for the purpose and with the intent that the title shall thereby pass. This principle is distinctly recognized in the case of Minchin v. Merrill, 2 Edw. Ch. 333, cited by the plaintiff’s counsel. In that case, as well as in several others of those cited, there was a complete delivery of the subject of the gift to a third party, in whose hands it was charged with the trust, the donor having parted with the possession and control. In none of them is there a denial of the principle above stated. In Howard v. Windham County Savings Bank, 40 Verm. 597, the deposit was made directly to the credit of the intended donee, making it a completed gift. The deposit by Knowles was entered in his own name and to his own credit. The legal title, and right to draw money so deposited, remains with the depositor. There was no direction or authority for the bank to pay it to the plaintiff. The form of the deposit does not imply such an intent; nor any obligation or right, on the part of the bank, so to pay it over. The declaration of trust is evidence that Knowles, the depositor, held the fund in some manner for the benefit of the person named as cestui que trust. But it did not, of itself, transfer to her the possession, nor the right of possession ; nor constitute a legal title in her. A deed, executed and put on record by the grantor, does not pass the title without some further act of delivery and acceptance. Maynard v. Maynard, 10 Mass. 456. Samson v. Thornton, 3 Met. 275. But if the grantor intend that the grantee shall receive it from the register, or if there be a previous agreement that the deed when made shall be so delivered at the registry, it will be effectual as *232a delivery. Shaw v. Hayward, 7 Cush. 170. So if there be an actual trust, and an obligation to make the transfer for the security of that trust, the continued possession of the instrument by the person who executed it, being also its proper custodian for the cestui que trust, is consistent with an assignment completed by delivery; and a legal delivery to pass the title will be inferred from very slight evidence. Moore v. Hazelton, 9 Allen 102. But there must be delivery or some equivalent act with intent to pass the title. Chase v. Breed, 5 Gray, 440. When the instrument is in fulfilment of a legal obligation, the intent may be inferred from that fact. Perhaps the same would be true of a moral obligation, such as provision for wife or child. Astreen v. Flanagan, 3 Edw. Ch. 279. We presume the decision in Witzel v. Chapin, 3 Bradf. 386, cited by the plaintiff, was made upon some considerations of this nature. That decison recognizes that it is a question of intent. See also Grangiac v. Arden, 10 Johns. 293; Goodrich v. Walker, 1 Johns. Cas. 251. Assuming in this case that the deposit and declaration of trust was a sufficient act of delivery to pass the title, if such were the intent, we think the facts agreed show clearly that 'such was not the intent of the depositor. On the contrary, it would appear that it was the intention of Knowles to deposit the whole money as his own ; and that the form of deposit was adopted for the sole purpose of evading a by-law of the bank and a provision of the statutes, limiting the amount that could be received from any one depositor to one thousand dollars.

1. The plaintiff contends that the written declaration of trust is conclusive, and objects to the competency of evidence to prove the facts relied on in defence; first, because it violates the rule excluding parol evidence to contradict or vary the terms of a written instrument. But that is a rule which applies to suits upon the instrument and between the parties to it. 1 Greenl. Ev. § 279. The plaintiff is no party to the contract between David Knowles and the defendant. She could maintain no action upon it. If she can recover at' all, it is because the money belongs to her, and the trust, being a mere naked trust for her benefit, is terminable at her pleasure. The contract of deposit is *233collateral to her title, which depends upon her relations with David Knowles. As to her and her claim, whether upon the bank or upon David Knowles, the contract is merely evidence by way of admission, subject to be controlled by any competent evidence as to the actual facts. In McCluskey v. Provident Institution for Savings, 103 Mass. 300, a deposit in the plaintiff’s own name was controlled by proof that the money deposited belonged in fact to the estate of her deceased husband.

2. For similar reasons the plaintiff cannot set up, as an estoppel against the defendant or against David Knowles, the by-law of the bank providing that “ any depositor may designate, at the time of making the deposit, the period for which he is desirous that the same shall remain in the bank, and the person for whose benefit the same is made ; and such depositor, and his legal representative, shall be bound by such conditions, by him voluntarily annexed to his deposit.” She is a stranger to that contract. She does not claim under it as his legal representative, but by a superior right, of which the contract is the evidence. There can be no estoppel where there is no mutuality or privity. 1 Greenl. Ev. §§ 189, 204, 211. Merrifield v. Parritt, 11 Cush. 590, 598. Sprague v. Oakes, 19 Pick. 455, 458. Worcester v. Green, 2 Pick. 425. Braintree v. Hingham, 17 Mass. 432. If, upon due presentation of the book, the money had been paid to her, this provision in the contract of deposit might have availed the bank as a defence against the depositor or his legal representatives. But it can have no force as an estoppel, except when so set up by the bank

3. Neither can the plaintiff avail herself of the fact that the alleged purpose of David Knowles, in making the deposits in the form he did, was an evasion or violation of law. Whatever effect any illegality on the part of Knowles might have upon his right to recover against the bank, it cannot operate to confer any title or legal right upon the plaintiff. The effect of illegality is to create a disability to sue, or to derive any legal right from the transaction affected by it. The plaintiff’s right to recover depends upon proof of an intent to make an absolute gift of this money to her The defendant is not precluded from *234disproving that intent because the evidence by which it is to be disproved tends also to show an unlawful act or purpose in a transaction between the defendant and David Knowles.

We have not considered the technical question whether any action could be maintained between these parties, for money so deposited, because that question seemed to be waived by the submission upon agreed facts, providing for a judgment for the plaintiff if the court shall be of opinion that she “ is entitled to said funds.”

Upon the facts stated, we are of opinion that she is not so entitled; and, according to the agreement, the plaintiff is to become Nonsuit.