Ohio Rev. Code § 147.40
Depositions taken in pursuance of sections 147.07 and 147.51 to 147.58 of the Revised Code by a person described in division (D) of section 147.51 of the Revised Code shall be taken on written interrogatories, on a written notice being given by the party desiring to take such depositions, which notice shall contain the names of the parties plaintiff and defendant, the court or tribunal in which the action is pending, the number of the regiment or battalion to which the witness belongs, and the names of the witnesses. The notice shall be served upon the adverse party, or his agent or attorney of record, or left at his usual place of abode, with a copy of the interrogatories, at least twenty days prior to the taking of such depositions. If the party on whom such notice is served desires to file cross-interrogatories, a copy of the them shall be served on the adverse party, or his agent or attorney of record, or left at his usual place of abode, within six days after the notice of taking depositions has been served, and the party giving the notice to take depositions, shall forward with his notice and interrogatories, the cross-interrogatories so served on him; and neither party, by himself, or his agent or attorney, shall be present at the time of taking such depositions.
R.C. §147.40