of petroleum products above and beneath the surface of the earth and their relative likelihood of ignition, and danger to life and property in the vicinity if ignited, when so stored. The master made elaborate findings of fact from which he inferred generally that it is more dangerous, from the standpoint of public safety, to .store underground than above, ga&.-Jine or kerosene in quantities of ten gallons or more. ÍYom this he drew the legal conclusion, adopted by the district court, that the ordinance was so arbitrary and capricious as not to be a permissible exercise of the police power.
We need not labor the point, long settled, that where legislative action is within the . scope of the police power, fairly debatable questions as to its reasonableness, wisdom and propriety are not for the determination of courts, but for that of the legislative body on which, rests the duty and responsibility of decision. Zahn v. Board of Public Works, 274 U. S. 325, 328; Hadacheck v. Los Angeles, 239 U. S. 394, 408-412, 413-414; Euclid v. Ambler Realty Co., 274 U. S. 365, 388; Jacobsen v. Massar chusetts, 197 U. S. 11, 30; Laurel Hill Cemetery v. San Francisco, 216 U. S. 358, 365; Cusack Co. v. City of Chicago, 242 U. S. 526, 530; Price v. Illinois, 238 U. S. 446, 451. To determine that the present ordinance was a permissible exercise of legislative discretion, as thus defined, we need not go beyond those findings of the master to which petitioners offer no serious challenge.
The master found that gasoline and kerosene stored in large quantities are dangerously inflammable substances, as we judicially know, Pierce Oil Corporation v. City of Hope, 248 U. S. 498, 500, which, when ignited, are a menace to life and property in the vicinity; that even with the use of the most modem safety devices, fires or. explosions of such storage tanks occur and that within the four years preceding the trial five disastrous fires of gasoline