Evelyn E. Cosgrove, Joe J. Kendrick, Lee E. Stewart and Douglas Tyler, employees of the County of Sacramento, on August 7, 1963, filed this proceeding in the superior court praying for a peremptory writ of mandate against the County of Sacramento and its board of supervisors to require compliance with section 63, article XIV (Labor and Employment) of its charter, which reads as follows: “In fixing compensation, the Board of Supervisors shall at least annually, by ordinance, provide in each instance for the payment of not less than the prevailing of general current rate of compensation or wages paid by private employers in the County of Sacramento for similar quality or quantity of service, in case such prevailing compensation or wages can be ascertained. Preference in all cases shall be given to Sacramento County residents. ’ ’

Prior to the filing of the petition, the board of supervisors had passed a salary ordinance for the year 1963, which was not pleasing to the petitioners. The original hearing eventuated in an order for the issuance of a peremptory writ, the trial judge saying in a memorandum:

Formal findings of fact and conclusions of law were filed by the court on September 24, 1964, and terms of a judgment entered on the same date followed the requirements of the above paragraph quoted from the memorandum of decision. The court specifically retained jurisdiction over the proceeding “. . . in order to permit review of the method of investigation conducted by the respondents under the said Writ of Mandate and the court directs the said respondents to file with the court a statement describing the method of investigation to be employed by respondents together with a statement containing respondents’ best estimation of the time required in the conduct of the investigation or the various phases of said investigation.” In the return, the county requested a postponement of the time “. . . relative to making a determination of the prevailing or general compensation or wages for the fiscal year 1963-64, sometime prior to January 1, 1965.” The request was granted and the investigation was postponed accordingly. On December 3, 1964, a notice was served and filed by counsel for the appellants that a motion would be made on December 16, 1964, to compel respondents to make an interim report in compliance with the peremptory writ of mandate. Almost a year later, on December 10, 1965, a hearing was finally held by the court sitting without a jury at which evidence was taken. On December 23, 1965, the court addressed a letter to both counsel saying, among other things:

On February 17, 1966, the court signed and filed an “Order and Findings Determining Compliance with Peremptory Writ of Mandate,” showing that, in the opinion of the court, the board of supervisors acted in accordance with the writ, saying, among other things:

It is doubtful, to say the least, whether or not there can be an effective appeal from a determination by a trial court that a peremptory writ of mandate issued by it has been complied with. Certainly, the court issuing the writ is best able to judge if it is satisfied with the performance as reported. However, we shall consider the merits of the appeal.

The evidence heard and examined by the court included a copy of Resolution No. 65-920 passed by the board of supervisors in due course, after its presumably attempted compliance with the peremptory writ of mandate; the resolution recites, among other things, that on the 24th day of September, 1964, the court “. . . directed this Board of Supervisors to examine all available data on salaries of Sacramento County employees to determine what salaries and wages were prevailing in private employment in Sacramento County just prior to the beginning of the 1963-64 fiscal year, and to determine in what classifications of County employment such data is unavailable; . . . ”

The resolution states that the board held public hearings on February 8, 1965, May 12, 1965, and August 23, 1965, “. . . for the purpose of obtaining all available data on salaries of Sacramento County Employees, pursuant to the said Order of the Superior Court; ...” and continues by saying that; “. . . additional information and data were presented to this Board of Supervisors in a report by the firm of Griffenhagen-Kroeger, Inc., a personnel consulting firm with extensive experience in conducting salary surveys; . . . ”

The document further says that the board “. . . has examined all available data and other relevant material on such salaries;” and proceeds to a determination that “. . . the salaries and wages for Sacramento County employees for the 1963-64 fiscal year were comparable to the salaries and wages prevailing in private employment in Sacramento County just prior to the-beginning of the 1963-64 fiscal year, . . .’’except for some seven classifications. As to those classifications, the salary ordinance which was adopted May 27, 1963, was amended to conform with the requirements of the peremptory writ as to the seven classifications. Certain other amendments were incorporated, and there was a finding that otherwise the rates of- compensation were confirmed as set forth in the original salary ordinance for the fiscal year 1963-64. The resolution was passed by the affirmative votes of all five supervisors.

Additional data was introduced at the final court hearing, including the Griffenhagen-Kroeger, Inc. report, which shows on its face considerable activity on the part of that firm in securing data required by the supervisors. There are, however, many blanks in the report, and the survey took only 10 days. to complete, notwithstanding the long delay by the board and in the court proceedings. It cannot fairly be said that the board and the court did not have substantial evidence, though not as full as it might be, to support the board’s resolution and the court’s determination.

It should be kept in mind that the board of supervisors, as the legislative branch of government in the county, is entitled to the exercise of discretion in judging facts which constitute the basis of its resolutions and ordinances. (See Collins v. City & County of San Francisco, 112 Cal.App.2d 719, 731 [ 247 P.2d 362 ].) And later, the trial court had the right to exercise discretion ón its own part in reaching its conclusions.

It seems to us that not much, if any, leeway is left to an appellate court to control the action of the trial court, when the trial court had before it substantial evidence upon which to act. As is said in 55 Corpus Juris Secundum, Mandamus, section 373, page 642: “Rules governing the scope or extent of review in civil actions generally on appeal . . . apply to appeal ... in mandamus proceedings. ’ ’

All presumptions usually made by an appellate court in considering appeals apply to a proceeding in mandamus. (55 C.J.S., Mandamus, § 373, (d), p. 646.) The judgment is presumed to be correct, and the burden is on appellant to show reversible error. (Murphy v. Retirement Board, 49 Cal.App.2d 58, 60 [ 121 P.2d 101 ] ; Williams v. Duffy, 32 Cal.2d 578, 582 [ 197 P.2d 341 ] (cert. denied, 335 U.S. 840 [ 93 L.Ed. 391 , 69 S.Ct. 57 ]). The presumption that public officials have performed their duty as required by law is applicable (Bandini Estate Co. v. Payne, 10 Cal.App.2d 623, 626 [ 52 P.2d 959 ]).

The duty of determining questions of fact in proceedings in mandate heard below is for the trial court. (Pacific Greyhound Lines v. Superior Court, 28 Cal.2d 61 [ 168 P.2d 665 ]; Dorothy v. Drapeau, 9 Cal.App.2d 280 [ 49 P.2d 343 ]; Bilcoff v. State Board of Medical Examiners, 90 Cal.App.2d 603 [203 P.2d 844]; Morgan v. City of Los Angeles, 91 Cal. App.2d 134, 138 [ 204 P.2d 375 ] ; Bogart v. Board of Medical Examiners, 105 Cal.App.2d 250 [ 233 P.2d 100 ] ; Stephenson v. Stoneman, 148 Cal.App.2d 456, 464 [ 306 P.2d 1000 ].)

Findings of the lower court will not be disturbed by the appellate court if they are based on substantial evidence even though the evidence is conflicting. (Drummey v. State Board of Funeral Directors, 13 Cal.2d 75, 88 [ 87 P.2d 848 ] ; Fickeisen v. Civil Service Com., 98 Cal.App.2d 419 [ 220 P.2d 605 ]; Borders v. Anderson, 204 Cal.App.2d 401, 410-411 [ 22 Cal.Rptr. 243 ].) The upper court will not attempt to weigh the evidence. (Faber v. Board Pension Comrs., 56 Cal.App.2d 825 [ 133 P.2d 404 ] ; Ford v. Civil Service Com., 161 Cal.App. 2d 692, 696 [ 327 P.2d 148 ]; Yen Eng v. Board of Bldg. & Safety Comrs., 184 Cal.App.2d 514, 521 [ 7 Cal.Rptr. 564 ].) In essence, it seems that the appellants wish this court to weigh the evidence and to overturn the conclusion of the trial court that the peremptory writ issued by that court has been complied with.

It is easy for anyone to criticize the long delay in reaching a final decision as well as the failure of the board of supervisors to make a more extensive report; all of these matters involve elements which conceivably might lead the voters of the county to arrive at an adverse judgment relative to some of the responsible officials. But, under the law, this court has no viable ground to order a reversal.

The judgment is affirmed.

Stone, J., and Gargano, J., concurred.