delivered the opinion of the court.

The description of the horse by age and color, and as being in the possession of the grantor at the time the deed of trust was executed, was sufficient. The deed of trust was not void for uncertainty as to the description of the horse. Kelly v. Reid, 57 Miss. 89 ; Nicholson v. Karpe, 58 Miss. 34.

There could be no exchange or substitution of other property in lieu of that described in the deed of trust, even by agreement of the parties, so as to render the deed of trust a lien upon the substituted property as against third persons having no actual notice of the agreement and substitution. The registration of the deed of trust was not constructive notice to third persons of the alleged' lien of appellants upon the substituted property. Jones on Chat. Mort., §§ 62, 71 ; Sharpe v. Pearce, 74 N. C. 690.

Porter did not own the mule in question when the deed of trust was executed, and if appellants have any right to the mule or its value it must exist under that provision of the deed of trust which attempted to convey all the property which the grantor might acquire by purchase or otherwise, after the deed of trust was executed. But this provision of the deed of trust, by reason of its generality and uncertainty in the description of the property sought to be conveyed by it, is inoperative against a subsequent purchaser. It is utterly void as to third persons. Miss. Valley Co. v. Chicago, etc., R. R. Co., 58 Miss. 896 ; Everman & Co. v. Robb, 52 Miss. 653; Jones on Chat. Mort., § 174. Affirmed.