LETTERS ROGATORY. A letter rogatory is an instrument sent in the name and by the authority of a judge or court to another, requesting the latter to cause to be examined, upon interrogatories filed in a cause depending before the former, a witness who is within the jurisdiction of the judge or court to whom such letters are addressed. In letters rogatory there is always an offer on the part of tbe court whence they issued, to render a similar service to the court to which they may be directed whenever required. Pet. C. C. Rep. 236.

2. Though formerly used in England in the courts of common law, 1 Roll. Ab. 530, pl. 13, they have been superseded by commissions of Dedimus potestatem, which are considered to be but a feeble substitute. Dunl. Pr. 223, n.; Hall's Ad. Pr. 37. The courts of admiralty use these letters, which are derived from the civil law, and are recognized by the law of nations. See Foelix, Dr. Intern. liv. 2, t. 4, p. 800; Denisart, h. t.