necessary to make the city a party to the controversy. Opinions General Counsel, 3 Pub. Serv. Comm. Reps. 436.

Two or more separate complaints cannot be combined in one proceeding without the consent of the complainants. Opinions General Counsel, 1 Pub. Serv. Comm. Reps. 107, 108.

2. Procedure of Commission. Upon the presentation of such complaint, the Commission shall consider whether or not in its judgment the same is of such a nature as prima facie to admit of relief or to justify redress under the law. For this purpose the Commission may make such ex parte investigation as it may deem proper. If the Commission is of the opinion that the complaint is not of the nature described, then the Commission shall notify the complainant, or his attorney, to this effect, and opportunity may be given the complainant to amend his complaint within a specied time. If in such event the complaint is not amended so as to set forth a cause which in the judgment of the Commission prima facie admits of relief or justifies redress, then the same shall be dismissed by the Commission.

If the Commission is of the opinion that such complaint, either as originally filed or as amended, is of such a nature as prima facie to admit of relief or to justify redress, as aforesaid, then an order shall be made as of course, directed to the person, firm or corporation complained of, and requiring that the matter complained of be satisfied, or that the complaint be answered in writing within twenty days from the service of said order, provided, however, that the Commission in its discretion may prescribe a less period of time for satisfaction or answer. Such order, together with a copy of the complaint, shall be served on the person, firm or

corporation complained of in any manner in which service is authoried to be made by Section II of the Public Service Commission Law.

3. Satisfaction of Complaint. If such person, firm or corporation shall satisfy the subject matter of such complaint, before the time allowed in the order for satisfaction or answer, then he or it shall notify the Commission to that effect. In such event, the Commission shalll thereupon transmit a copy of such notice to the complainant or his attorney, and no further action need be taken.

4. Answer to Complaint. If satisfaction be not made as aforesaid, then the person, firm or corporation complained of must, within the time specified in the order, file an answer to the complaint, with an admission of service of copy endorsed thereon by the complainant or his attorney.

5. Hearings. If satisfaction be not made as aforesaid, then after the expiration of the time allowed for answer, and whether the answer has been filed or not, the Commission shall determine whether or not relief should be granted, and for this purpose may make such investigation and hold such hearings as it may deem necessary.

6. Final Order. The Commission shall then make and file an order either dismissing the petition, or directing the person, firm or corporation complained of to satisfy the cause of complaint in the manner specified by the Commissiion and authorized by law.

7. Amendments. Amendments to any complaint, petition, answer or other paper filed in any hearing, in

vestigation or proceeding, may be permitted by the Commission at its discretion.

Under this section a complainant may discontinue a proceeding and another take his place and prosecute the case as the former complainant has done. This involves the making of entire new parties, but proceedings before the Commission do not fall within the provisions of Sec. 41, Article 75 of the Maryland Code of Public General Laws, which declare that in no case of amendment can entirely new parties, either plaintiffs or defendants, be made. Opinions General Counsel, 3 Pub. Serv. Comm. Reps. 425.

8. Hearing in the Nature of Demurrer. A person, firm or corporation complained of, who deems the complaint insufficient to show a breach of legal duty, may, instead of answering or formally demurring, serve on the complainant, or his attorney, and the Commission notice that he or it demands a hearing on the complaint, and in such case the facts stated in the complaint will be deemed admitted. The filing of an answer, however, will not be deemed an admission of the sufficiency of the complaint, but a motion to discuss for insufficiency may be made at the hearing.

This rule does not mean that upon service of the notice required the whole case will be disposed of as if it turned upon a technical demurrer in a common law action or in an equity proceeding. Such notice does not take from the Commission its independent powers of investigation, nor prevent the complainant from bringing forward evidence showing that his complaint could be readily perfected by amendment. Opinions General Counsel, 3 Pub. Serv. Comm. Reps. 423.

An application for a rehearing will be granted where new and additional evidence can be offered. Opinions General Counsel, 3 Pub. Serv. Comm. Reps. 434.

9. Special Requirements. The provisions in this rule contained as to the form and contents of petitions and complaints shall not be taken to dispense with any additional requirements which may be hereinafter provided for special cases.

RULE IV.

HEARINGS AND INVESTIGATIONS.

I. Stipulations. The parties to any hearing, investigation or other proceeding before the Commission may, by stipulation in writing filed with the Commission, agree upon the facts or any of the facts involved therein, which stipulation, if filed, shall be regarded and used as evidence at such hearing, investigation or other proceeding. The Commission may, nevertheless, require such additional evidence as it may deem necessary.

Character of Testimony. Except where stipulations are filed as above, the witnesses whose testimony may be desired at any hearing, investigation or proceeding before the Commission, or before any one of the Comissioners, as authorized by Section 4 of the Public Service Commission Law, shall testify orally and under oath, unless the Commission or Commissioner for good cause shown deems it proper in special cases that written evidence, under affidavit or otherwise, be submitted.

3. Subpoenas. Subpoenas for witnesses may be signed and issued by the Secretary or by the Commission or a Commissioner, and may be served by any person of full age designated by the Commission, or by a Commissioner or the Secretary, or through the Sheriff's office of any city or county of the State.

The Commission may cause subpoenas and subpoenas duces tecum to be issued upon its own motion, or upon the application of any party to any hearing or investigation; but subpoenas duces tecum will not be issued upon application, unless such application is in writing and describes the books, papers or other documents to be produced.

4. Evidence. The complainant should in all cases establish the facts alleged to constitute a violation of the law, unless the defendant admits the same or fails to answer the complaint, and upon request by the complainant, the Commission may assign counsel to appear for him or them, in conformity with Chapter 563 of the Acts of the General Assembly of Maryland, 1912. The defendant must also give evidence of the facts alleged in the answer, unless admitted by the complainant, and must fully disclose his or its defense at the hearing.

In case of failure to answer, the Commission will take such proof of the facts as may be deemed proper and reasonable and make such order thereon as the circumstances of the case require.

5. Documentary Evidence. In all cases where documentary evidence is offered, the Commission, in its discretion, in lieu of requiring the originals thereof to be filed, may accept true copies of such evidence or of such parts of the same as may be relevant, or may require such evidence to be transcribed as part of the record.

6. Briefs. The Commission may, whenever it deems desirable, require printed or typewritten briefs to be filed on behalf of any party or parties to any investigation, hearing or other proceeding. Such briefs shall contain