Without question, prior to expiration of an eligible list, the life of the list may be extended up to the statutory four-year period (Matter of Roske v Keyes, 46 A.D.2d 366, 368; Uniformed Fireman's Benevolent Assn. v Herten, 23 A.D.2d 788, 789). Extension beyond the four-year maximum is also permissible, but then express statutory authority is essential (see Ciaccia v Board of Educ., 271 N.Y. 336, 339; Brown v Craig, 209 App. Div. 11, 13-14; Matter of Woods v Finegan, 246 App. Div. 271, 273). Once a list has expired, however, even the Legislature is, under the Constitution, powerless to revive it (Ciaccia v Board of Educ., 271 N.Y. 336, 339, supra; Hurley v Board of Educ., 270 N.Y. 275, 279-280; see N Y Const, art V, § 6).

5. In Matter of Woods v. Finegan, 246 App. Div. 271, 272, 285 N.Y. S. 277, 279, involving the life of a civil service eligible list and the question of whether or not it could be directly or indirectly extended beyond a statutory 4-year period, the court said: "The petitioner is not aided by the fact that in 1927 he passed a civil service examination and was thereafter placed upon the eligible list for the position of inspector of foods (meat and poultry), as it appears that in the year 1932, and before petitioner's name was reached for certification or appointment, it had expired by operation of law.

Their failure to act at that time disposed of their right to the relief which they now request. Matter of Woods v. Finegan, 246 App.Div. 271, 272, 285 N.Y.S. 277; State ex rel. Warmus v. Seattle, 2 Wash.2d 420, 423, 97 P.2d 1095; see Foley v. Director of Civil Service, 316 Mass. 550, 552, 56 N.E.2d 9.

It should be noted that duly adopted rules by the Commission have the force and effect of law (Civil Service Law, § 20, subd. 2; Matter of Woods v. Finegan, 246 App. Div. 271, 273). The Legislature could hardly have intended that every internal change or variation, no matter how slight, which did not transgress the bounds of statutory limitation, must be made in accordance with the requirements of section 20 Civ. Serv. of the Civil Service Law.

In our view, the administration of civil service is not capable of such precise classification. It is true that any issue substantially affecting the merit system is a matter of primary State concern because the whole fabric of civil service depends upon adherence to the principle of the merit system based upon competitive examinations (N.Y. Const., art. V, § 6; Matter of Meenagh v. Dewey, 286 N.Y. 292; Matter of Friedman v. Finegan, 268 N.Y. 93). Yet, as to the administration of the Civil Service Law, the functions of both State and local (either county or municipal) commissions are recognized as separate, each with its own prerogatives (Civil Service Law, art. II, §§ 5-9, 15-27; General City Law, § 20, subd. 18; Matter of Ebling v. New York State Civ. Serv. Comm., 305 N.Y. 221; Matter of Woods v. Finegan, 246 App. Div. 271). The municipal commission is not a mere appendage to the State system but is an integral and yet independent facility enjoying substantial autonomy as to singularly local problems and solutions.

Commission has the power to prescribe, amend and enforce suitable rules to carry out the provisions of the Civil Service Law and of section 6 of article V of the New York State Constitution, including rules for examinations, appointments, promotions, transfers, etc. (Civil Service Law, § 20; Rules and Regulations City Civ. Serv. Comm., rule II). Such rules when properly adopted shall have the force and effect of law (Civil Service Law, § 20, subd. 2; Matter of Woods v. Finegan, 246 App. Div. 271; Matter of Cuzzivoglio v. Hamlin, 202 N.Y.S.2d 402, affd. 13 A.D.2d 614, motion for leave to appeal denied 13 A.D.2d 899). Pursuant to the power vested in it Commission promulgated rule 4.

The rule states: "In examinations for promotion to positions in the Police Service * * * the service record shall be a continuation of the last record furnished in cases where the candidate has obtained a promotion as the result of a promotion examination; * * *". This wording, we think, is vague and indefinite. While the Rules of the Municipal Civil Service Commission have the force and effect of law (Civil Service Law, §§ 6, 8; Matter of Poss v. Kern, 263 App. Div. 320; Matter of Woods v. Finegan. 246 A D 271, 272; Matter of Wittekind v. Kern, 170 Misc. 939, affd. 256 App. Div. 918, affd. 281 N.Y. 701), to be valid and binding they should be couched in plain and unambiguous language. Defendants construe the quoted language to mean that petitioner's service record as established at his first promotion examination, to wit, that for the rank of sergeant, is to be continued for all future promotion examinations in which he participates.

The municipal civil service commission was without authority to declare eligible those who did not receive a rating of seventy-five per cent or over in each part of the technical written test, for such action violated subdivision 3 of section V of rule V of the Rules of the Municipal Civil Service Commission, which reads as follows: "Unless otherwise specified, a candidate must receive not less than 50 percent in any required subject and a general average of not less than 70 percent to be eligible for certification and appointment, except that candidates for positions of a scientific, professional or technical character must obtain a rating of 75 percent in each technical subject." It is well settled that the municipal civil service commission is bound by its own rules, which, under the statute, have the full force and effect of law. (Civ. Serv. Law, § 6, subd. 1; Matter of Woods v. Finegan, 246 App. Div. 271; Matter of O'Brien v. Delaney, 255 id. 385; affd., 280 N.Y. 697; Matter of Wittekind, v. Kern, 170 Misc. 939; affd., 256 App. Div. 918; affd., 281 N.Y. 701.) As previously pointed out, candidates were required to take both Part I and Part II of the written examination.

When that list expired, the rights and privileges of petitioners under the Civil Service Law and their qualifications as eligibles expired. ( Matter of Woods v. Finegan, 246 A.D. 271; Brown v. Craig, 209 A.D. 11.) By the same token, they were deprived of any qualification to contest the validity of any appointments to civil service positions, for which they can demonstrate no personal claim in a proceeding such as this.

" The Appellate Division of this Department has recently held to the same effect in Matter of Woods v. Finegan ( 246 A.D. 271). In New York Legislative Documents (N.Y. Legis.