In such case the service shall be deemed to have been effected when the letter would arrive in ordinary course of post.

Service when person summoned cannot be found Service when person summoned cannot be found.-Where the person summoned cannot by the exercise of due diligence be found, the summons may be served by leaving one of the duplicates for him with some adult male member of his family and the person with whom the summons is so left shall, if so required by the serving officer, sign a receipt therefor on the back of the other duplicate.