Order dismissing petition for -a mandamus order directing the reinstatement of petitioner in the position of park engineer and the payment of back salary unanimously affirmed, with costs, as a matter of law and not in the exercise of discretion. Although the suspension of petitioner on March 31, 1932, while another employee junior to him in service was retained, was improper, petitioner waived his right to reinstatement at that time through his failure to seek promptly the remedy of mandamus. (Thoma v. City of New York, 263 N. Y. 402; People ex rel. Vanderhoof v. Palmer, 3 App. Div. 389; People ex rel. Young v. Collis, 6 id. 467; Matter of MacMaster v. Harvey, 239 id. 553.) There was likewise laches in petitioner’s failure to proceed promptly in mandamus upon his reinstatement in a lower salary grade on June 16,1932, upon his reduction to the status of laborer in February, 1933, and upon his appointment in salary grade 6 on April 1, 1933. In addition, there was no proof that at the time of petitioner’s reinstatement in June, 1932, any vacancy existed at a higher grade, and no proof that at the time when petitioner was reduced to the status of laborer in February, 1933, other employees then in the same grade were not similarly reduced in rank and salary. Petitioner’s final suspension in March, 1934, was *1021proper since all other engineers in the same classification and grades were likewise suspended. Petitioner cannot complain that some engineers in grade 7 were retained at that time, since each grade is to be considered as a separate entity for seniority purposes (Matter of Skrocki v. Greene, 242 App. Div. 226; Matter of Smith v. Greene, 247 id. 425), and petitioner had acquiesced in his appointment to grade 6. Appeal from decision dismissed. Present — Hagarty, Carswell, Adel, Taylor and Close, JJ. [See, also, 246 App. Div. 635; 271 N. Y. 542.]