There was a decree below for the plaintiff. The trial court was of opinion that the ■ plea of res judicata should be overruled. We think this was error.

A careful examination of the record convinces us that the action at law between the parties was upon the same cause oC action as that offered to sustain the present suit, in other words, that there was a single cause of action, and in such circumstances the rule of res judicata is applicable. On this subject, see Baltimore S. S. Co. v. Phillips, 274 U. S. 316, 319, 320, 47 S. Ct. 600, 71 L. Ed. 1069, and U. S. v. Moser, 266 U. S. 236, 241, 45 S. Ct. 66, 69 L. Ed. 262. In addition to this, we think it is doubtful if the substituted service of process on the defendant Violet S. Hussein was valid. See Dexter v. Lichliter, 24 App. D. C. 222.

The decree of the lower court will therefore be reversed, and the cause remanded to that court, with instructions to dismiss the bill.

Eeversed.