4. The Writ or Process.—
Upon a libel being properly filed in the office of a clerk of a district court of the United States, a writ of attachment is prepared and delivered to the marshal which commands him to arrest and take the ship, goods or other things into his possession for safe custody; and to cause public notice thereof, and of the time fixed for the return of the writ and the hearing of the cause, to be given in such newspaper within the district as the court shall order. It is then the duty of the marshal to obey the writ, arrest the property and give due notice according to law.