Cotton, L.J., stated the law in these words: "The true rule in my opinion is, that if there is any agreement between the principals with reference to the contract guaranteed, the surety ought to be consulted, and that, if he has not consented to the alteration, although in cases where it is without inquiry evident that the alteration is unsubstantial, or that it cannot be otherwise than beneficial to the surety, the surety may not be discharged; ), Yet, that if it is not self evident that (1) ; (1862) 4 De G. F. & J. 365 ; (2) 79 the alteration is unsubstantial, or one which cannot be prejudicial to the surety, the Court will not, in an action against the suerty, go into an inquiry as to the effect of the alteration. . " To this statement of the law, must be added the 'dissent of Brett, L.J., who stated that the surety in that case was not raleased observing that the doctrine of release of sureties was carried far enough and that lie would not carry it any further.