Each defendant assigns as error the disallowance of its motion for a compulsory nonsuit. We consider these assignments of error separately because the defendants urge different reasons to sustain their respective positions.

The High Penn Oil Company contends that the evidence is not sufficient to establish either an actionable or an abatable private nuisance. This contention rests on a twofold argument somewhat alternative in character. The High Penn Oil Company asserts primarily that private nuisances are classified as nuisances per se or at law, and nuisances per accidens or in fact; that when one carries on an oil refinery upon premises in his rightful occupation, he conducts a lawful enterprise, and for that reason does not maintain a nuisance per se or at law; that in such case the oil refinery can constitute a nuisance per accidens or in fact to the owner of neighboring land if, and only if, it is constructed or operated in a negligent manner; that there was no testimony at the trial tending to show that the oil refinery was constructed or operated in a negligent manner; and that consequently the evidence does not suffice to establish the existence of either an actionable or an abatable private nuisance. The High Penn Oil Company insists secondarily that the plaintiffs in a civil action can recover only on the case presented by their complaint; that the complaint in the instant action states a cause of action based solely on negligence; that there was no testimony at the trial indicating that the oil refinery was constructed or operated in a negligent manner; and that consequently the evidence is not sufficient to warrant the relief sought and obtained by the plaintiffs, even though it may be ample to establish a nuisance.

*191. The case on appeal discloses some substantial reasons for contesting .the soundness of tbe thesis of the High Penn Oil Company that there was no testimony at the trial tending to show that the oil refinery was constructed or operated in a negligent manner. Even expert witnesses for the defendants testified in substance on cross-examination that the oil refinery would not emit gases or odors in annoying quantities if it were “operated properly.” We would be compelled, however, to reject the argument of the High Penn Oil Company on the present aspect of the appeal even if we should accept at face value its thesis that there was no testimony at the trial tending to show that the oil refinery was constructed or operated in a negligent manner.

The High Penn Oil Company asserts with complete correctness that private nuisances may he classified as nuisances per se or at law, and nuisances per accidens or in fact. A nuisance per se or at law is an act, occupation, or structure which is a nuisance at all times and under any circumstances, regardless of location or surroundings. 39 Am. Jur., Nuisances, section 11; 66 C.J.S., Nuisances, section 3. Nuisances per accidens or in fact are those which become nuisances by reason of their location, or by reason of the manner in which they are constructed, maintained, or operated. Swinson v. Realty Co,, 200 N.C. 276, 156 S.E. 545; Cherry v. Williams, 147 N.C. 452, 61 S.E. 267, 125 Am. S. E. 566, 15 Ann. Gas. 715; Dargan v. Waddill, 31 N.C. 244, 49 Am. D. 421. The High Penn Oil Company also asserts with complete correctness that an oil refinery is a lawful enterprise and for that reason cannot be a nuisance per se or at law. Waier v. Peerless Oil Co., 265 Mich. 398, 251 N.W. 552; Midland Empire Packing Co. v. Yale Oil Corp. of S. D., 119 Mont. 36, 169 P. 2d 732; Purcell v. Davis, 100 Mont. 480, 50 P. 2d 255. The High Penn Oil Company falls into error, however, when it takes the position that an oil refinery cannot become a nuisance per accidens or in fact unless it is constructed or operated in a negligent manner.

Negligence and nuisance are distinct fields of tort liability. 39 Am. Jur., Nuisances, section 4. While the same act or omission may constitute negligence and also give rise to a private nuisance per accidens or in fact, and thus the two torts may coexist and be practically inseparable, a private nuisance per accidens or in fact may be created or maintained without negligence. Butler v. Light Co., 218 N.C. 116, 10 S.E. 2d 603; Swinson v. Realty Co., supra; 39 Am. Jur., Nuisances, section 24; 65 C.J.S., Negligence, section 1; 66 C.J.S., Nuisances, section 11. Most private nuisances per accidens or in fact are intentionally created or maintained, and are redressed by the courts without allegation or proof of negligence. Godfrey v. Power Co., 190 N.C. 24, 128 S.E. 485; Moran v. Pittsburgh-Des Moines Steel Co., 166 F. 2d 908; King v. Columbian Carbon Co., 152 F. 2d 636; E. Rauh & Sons Fertilizer Co. v. Shreffler, *192139 F. 2d 38; Actiesselskabet Ingrid v. Central R. Co., 216 F. 72, L.R.A. 1916B, 716; Terrell v. Alabama Water Service Co., 245 Ala. 68, 15 So. 2d 727; Beam v. Birmingham Slag Co., 243 Ala. 313, 10 So. 2d 162; Gus Blass Dry Goods Co. v. Reinman & Wolfort, 102 Ark. 287, 143 S.W. 1087; Curtis v. Kastner, 220 Cal. 185, 30 P. 2d 26; Kafka v. Bozio, 191 Cal. 746, 218 P. 753, 29 A.L.R. 833; Swift & Co. v. Peoples Coal & Oil Co., 121 Conn. 579, 186 A. 629; Cunningham v. Wilmington Ice Mfg. Co. (Del. Super.), 2 W. W. Hair. 229, 121 A. 654; Dilucchio v. Shaw (Del. Super.), 1 W. W. Harr. 509, 115 A. 771; District of Columbia v. Totten, 55 App. D. C. 312, 5 F. 2d 374, certiorari denied 269 U.S. 562, 46 S. Ct. 21, 70 L. Ed. 412; Pitner v. Shugart Bros., 150 Ga. 340, 103 S.E. 791, 11 A.L.R. 1399; Laflin, & R. Powder Co. v. Tearney, 131 Ill. 322, 23 N.E. 389, 7 L.R.A. 262, 19 Am. S. R. 34; Menolascino v. Superior Felt & Bedding Co., 313 Ill. App. 557, 40 N.E. 813; City of Lebanon v. Twiford, 13 Ind. App. 384, 41 N.E. 844; Ryan v. City of Emmetsburg, 232 Iowa 600, 4 N.W. 2d 435; Andrews v. Western Asphalt Paving Corporation, 193 Iowa 1047, 188 N.W. 900; Bowman v. Humphrey, 132 Iowa 234, 109 N.W. 714, 6 L.R.A. (N.S.) 1111, 11 Ann. Cas. 131; Carlson v. Mid-Continent Development Co., 103 Kan. 464, 173 P. 910, L.R.A. 1918F, 318; Bailey v. Kelly, 93 Kan. 723, 145 P. 556, L.R.A. 1916D, 1220, 86 Kan. 911, 122 P. 1027, 39 L.R.A. (N.S.) 378; Rogers v. Bond Bros., 279 Ky. 239, 130 S.W. 2d 22; O’Neal v. Southern Carbon Co., 211 La. 1075, 31 So. 2d 216; Foley v. H. F. Farnham Co., 135 Me. 29, 188 A. 708; Toy v. Atlantic Gulf Pacific Co., 176 Md. 197, 4 A. 2d 757; Bern v. Boston Consol. Gas Co., 310 Mass. 651, 39 N.E. 2d 576; Ferriter v. Herlihy, 287 Mass. 138, 191 N.E. 352; Hakkila v. Old Colony Broken Stone & Concrete Co., 264 Mass. 447, 162 N.E. 895; Wilkinson v. Detroit Steel & Springs Works, 73 Mich. 405, 41 N.W. 490; H. Christianson & Sons v. City of Duluth, 225 Minn. 475, 31 N.W. 2d 270; Johnson v. Fairmont, 188 Minn. 451, 247 N.W. 572; Pearson v. Kansas City, 331 Mo. 885, 55 S.W. 2d 485; Boyle v. Neisner Bros., 230 Mo. App. 90, 87 S.W. 2d 227; Jeffers v. Montana Power Co., 68 Mont. 114, 217 P. 652; Toft v. City of Lincoln, 125 Neb. 498, 250 N.W. 748; Brownsey v. General Printing Ink Corporation, 118 N.J.L. 505, 193 A. 824; Dixon v. New York Trap Rock Corporation, 293 N.Y. 509, 58 N.E. 2d 517, motion for reargument denied, 294 N.Y. 654, 60 N.E. 2d 385; Hogle v. H. H. Franklin Mfg. Co., 199 N.Y. 388, 92 N.E. 794, 32 L.R.A. (N.S.) 1038, affirming judgment, 128 App. Div. 403, 112 N.Y.S. 881; Bohan v. Port Jervis Gas-Light Co., 122 N.Y. 18, 25 N.E. 246, 9 L.R.A. 711; Kremer v. City of Uhrichsville, 67 Ohio App. 61, 35 N.E. 2d 973; Ohio Stock Food Co. v. Gintling, 22 Ohio App. 82, 153 N.E. 341; Vantier v. Atlantic Refining Co., 231 Pa. 8, 79 A. 814; Gavigan v. Atlantic Refining Co., 186 Pa. 604, 40 A. 834; Rogers v. Philadelphia Traction Co., 182 Pa. *193473, 38 A. 399, 61 Am. S. R. 716; Rose v. Standard Oil Co. of New York, 56 R.I. 272, 185 A. 251, reargument denied, 56 R.I. 472, 188 A. 71; Braun v. Iannotti, 54 R.I. 469, 175 A. 656; Frost v. Berkeley Phosphate Co., 42 S.C. 402, 20 S.E. 280, 46 Am. S. R. 736, 26 L.R.A. 693; Cuffman v. City of Nashville, 26 Tenn. App. 367, 175 S. W. 2d 331; Soap Corp. of America v. Balis (Tex. Civ. App.), 223 S.W. 2d 957; Columbian Carbon Co. v. Tholen (Tex. Civ. App.), 199 S.W. 2d 825; G. L. Webster Co. v. Steelman, 172 Va. 342, 1 S.E. 2d 305; Terrell v. Chesapeake & O. R. Co., 110 Va. 340, 66 S.E. 55, 32 L.R.A. (N.S.) 371; Bartel v. Ridgefield Lumber Co., 131 Wash. 183, 229 P. 306, 37 A.L.R. 683; Flanagan v. Gregory & Poole, Inc., .... . W. Va. ...., 67 S.E. 2d 865; Wilson v. Phoenix Powder Mfg. Co., 40 W. Va. 413, 21 S.E. 1035, 52 Am. S. R. 890; Dolata v. Berthelet Fuel & Supply Co., 254 Wis. 194, 36 N.W. 2d 97; Brown v. Milwaukee Terminal Ry. Co., 199 Wis. 575, 227 N.W. 385, reversing 199 Wis. 575, 224 N.W. 748.

Tbe laiv of private nuisance rests on tbe concept embodied in tbe ancient legal maxim Sic utere tuo ut alienum non laedas, meaning, in essence, tbat every person should so use bis own property as not to injure that of another. Barger v. Barringer, 151 N.C. 433, 66 S.E. 439, 25 L.R.A. (N.S.) 831, 16 Ann. Cas. 472; Tennessee Coal, Iron & R. Co. v. Hartline, 244 Ala. 116, 11 So. 2d 833; Beam v. Birmingham Slag Co., supra; G. L. Webster Co. v. Steelman, supra. As a consequence, a private'll nuisance exists in a legal sense when one makes an improper use of bis T own property and in that way injures tbe land or some incorporeal right j of one’s neighbor. King v. Ward, 207 N.C. 782, 178 S.E. 577; Holton v. Oil Co., 201 N.C. 744, 161 S.E. 391; 39 Am. Jur., Nuisances, section 3.

Much confusion exists in respect to tbe legal basis of liability in tbe law of private nuisance because of tbe deplorable tendency of the courts to call everything a nuisance, and let it go at tbat. Moran v. Pittsburgh-Des Moines Steel Co., supra; Taylor v. City of Cincinnati, 143 Ohio St. 426, 55 N.E. 2d 724. The confusion on this score vanishes in large part, however, when proper heed is paid to tbe sound propositions tbat private nuisance is a field of tort liability rather than a single type of tortious conduct; tbat tbe feature which gives unity to this field of tort liability is tbe interest invaded, namely, the interest in tbe use and enjoyment of land; tbat any substantial non-trespassory invasion of another’s interest in the private use and enjoyment of land by any type of liability forming conduct is a private nuisance; that the invasion which subjects a person to liability for private nuisance may be either intentional or unintentional; that a person is subject to liability for an intentional invasion when his conduct is unreasonable under the circumstances of the particular case; and that a person is subject to liability for an unintentional invasion when his conduct is negligent, reckless or ultrahazardous. See *194Scope and Introduction Note to Chapter 40, American Law Institute’s Restatement of the Law of Torts; Moran v. Pittsburgh-Des Moines Steel Co., supra; Soukoup v. Republic Steel Corp., 78 Ohio App. 87, 66 N.E. 2d 334; 66 C.J.S., Nuisances, section 8.

An invasion of another’s interest in the use and enjoyment of land is intentional in the law of private nuisance when the person whose conduct is in question as a basis for liability acts for the purpose of causing it, or knows that it is resulting from his conduct, or knows that it is substantially certain to result from his conduct. Restatement of the Law of Torts, section 825; E. Rauh & Sons Fertilizer Co. v. Shreffler, supra; Harman v. City of Buffalo, 214 N.Y. 316, 108 N.E. 451; Bohan v. Port Jervis Gas-Light Co., supra; Columbian Carbon Co. v. Tholen, supra. A person who intentionally creates or maintains a private nuisance is liable for the resulting injury to others regardless of the degree of care or skill exercised by him to avoid such injury. Judson v. Los Angeles Suburban Gas Co., 157 Cal. 168, 106 P. 581, 26 L.R.A. (N.S.) 183, 21 Ann. Cas. 1247; Blackman v. Iowa Union Electric Co., 234 Iowa 859, 14 N.W. 2d 721; Susquehanna Fertilizer Co. v. Spangler, 86 Md. 562, 39 A. 270, 63 Am. S. R. 533; Robinson v. Westman, 224 Minn. 105, 29 N.W. 2d 1; Bollinger v. Mungle (Mo. App.), 175 S.W. 2d 912; Powell v. Brookfield Pressed Brick & Tile Mfg. Co., 104 Mo. App. 713, 78 S.W. 646; Wallace & Tiernan Co. v. U. S. Cutlery Co., 97 N. J. Eq. 408, 128 A. 872, decree affirmed, 98 N. J. Eq. 699, 130 A. 920; Monaco v. Comfort Bus Line, 134 N.J.L. 553, 49 A. 2d 146; Jutte v. Hughes, 67 N.Y. 267; Whaley v. Citizens Nat. Bank, 28 Pa. Super. 531; Western Texas Compress Co. v. Williams (Tex. Civ. App.), 124 S.W. 493; Flanagan v. Gregory & Poole, Inc., supra; 39 Am. Jur., Nuisances, section 24. One of America’s greatest jurists, the late Benjamin N. Cordozo, made this illuminating observation on this aspect of the law: “Nuisance as a con-I cept of the law has more meanings than one. The primary meaning does not involve the element of negligence as one of its essential factors. One acts sometimes at one’s peril. In such circumstances, the duty to desist is absolute whenever conduct, if persisted in, brings damage to another. Illustrations are abundant. One Avho emits noxious fumes or gases day by day in the running of his factory may be liable to his neighbor though he has taken all available precautions. He is not to do such things at all, whether he is negligent or careful.” McFarlane v. City of Niagara Falls, 247 N.Y. 340, 160 N.E. 391.

When the evidence is interpreted in the light most favorable to the plaintiffs, it suffices to support a finding that in operating the oil refinery the High Penn Oil Company intentionally and unreasonably caused noxious gases and odors to escape onto the nine acres of the plaintiffs to such a degree as to impair in a substantial manner the plaintiffs’ use and *195enjoyment of tbeir land. This being so, tbe evidence is ample to establish tbe existence of an actionable private nuisance, entitling tbe plaintiffs to recover temporary damages from tbe High Penn Oil Company. Webb v. Chemical Co., 170 N.C. 662, 87 S.E. 633; Duffy v. Meadows, 131 N.C. 31, 42 S.E. 460; Hyatt v. Myers, 71 N.C. 271; Bohan v. Port Jervis Gas-Light Co., supra; 39 Am. Jur., Nuisances, sections 58, 59; 66 C.J.S., Nuisances, sections 23, 60. When tbe evidence is taken in tbe light most favorable to tbe plaintiffs, it also suffices to warrant tbe additional inferences that tbe High Penn Oil Company intends to operate tbe oil refinery in tbe future in tbe same manner as in tbe past; that if it is permitted to carry this intent into effect, tbe High Penn Oil Company will hereafter cast noxious gases and odors onto tbe nine acres of tbe plaintiffs with such recurring frequency and in such annoying density as to inflict irreparable injury upon tbe plaintiffs in tbe use and enjoyment of tbeir borne and tbeir other adjacent properties; and that tbe issuance of an appropriate injunction is necessary to protect tbe plaintiffs against tbe threatened irreparable injury. This being true, tbe evidence is ample to establish tbe existence of an abatable private nuisance, entitling tbe plaintiffs to such mandatory or prohibitory injunctive relief as may be required to prevent'the High Penn Oil Company from continuing tbe nuisance. Barrier v. Troutman, 231 N.C. 47, 55 S.E. 2d 933; Pruitt v. Bethell, 174 N.C. 454, 93 S.E. 945; Hyatt v. Myers, supra; Hedrick v. Tubbs, 120 Ind. App. 326, 92 N.E. 2d 561; Kepler v. Industrial Disposal Co., 84 Ohio App. 80, 85 N.E. 2d 308; 39 Am. Jur., Nuisances, sections 156, 158, 172; 66 C.J.S., Nuisances, sections 115, 116, 134.

Tbe contention of tbe High Penn Oil Company that tbe complaint states a cause of action based solely on negligence is untenable. To be sure, tbe plaintiffs assert that tbe defendants were “negligent and careless” in specified particulars in constructing and operating tbe oil refinery. When tbe complaint is construed as a whole, however, it alleges facts which show a private nuisance resulting from an intentional and unreasonable invasion of tbe plaintiffs’ interest in tbe use and enjoyment of tbeir land. Bohan v. Port Jervis Gas-Light Co., supra; Braun v. Iannotti, supra; Flanagan v. Gregory & Poole, Inc., supra; 39 Am. Jur., Nuisances, section 142.

For tbe reasons given, tbe evidence is sufficient to withstand tbe motion of tbe High Penn Oil Company for a compulsory nonsuit.

Tbe reverse is true with respect to tbe motion of tbe Southern Oil Transportation Company. Tbe complaint charges tbe Southern Oil Transportation Company with responsibility for tbe nuisance alleged solely upon tbe theory that it actively participated in tbe construction and operation of tbe oil refinery. According to all tbe evidence, tbe Southern Oil Transportation Company bad no part in these undertakings. *196The evidence for the plaintiffs indicates that the Southern Oil Transportation Company was the absolute owner of the land on which the oil refinery stands until 10 September, 1952; that it possessed the consequent power to control the use of the land until that date; and that it knowingly permitted the High Penn Oil Company to operate the oil refinery upon the land owned and controlled by it down to 10 September, 1952, in such a manner as to constitute a nuisance despite notice and protest from the plaintiffs. The complaint does not invoke this evidence as a foundation of liability on the part of the Southern Oil Transportation Company for the nuisance alleged. McManus v. Railroad, 150 N.C. 655, 64 S.E. 766; Maynard v. Carey Const. Co., 302 Mass. 530, 19 N.E. 2d 304; 66 C.J.S., Nuisances, section 88. These things being true, there is a fatal variance between the pleading and the proof of the plaintiffs with respect to the Southern Oil Transportation Company, and the action ought to have been involuntarily nonsuited as to the Southern Oil Transportation Company in the court below under the fundamental procedural rule that a recovery cannot be had in a civil action on the basis of matters alleged, but not proved, or proved but not alleged. Wilkins v. Finance Co., 237 N.C. 396, 75 S.E. 2d 118; 66 C.J.S., Nuisances, sections 126, 147.

'While the evidence is ample to overcome its motion for a compulsory nonsuit, the High Penn Oil Company is entitled to have the cause tried anew because of prejudicial error in the instruction covered by its sixteenth assignment of error. This portion of the charge is thus phrased: “The court charges you . . . that before you can find that the defendants operated and maintained their plant and premises as a nuisance, you must find from the evidence and by the greater weight thereof that their operation injuriously affected the health, safety, morals, good order, or general welfare of the community, or infringed upon the property rights of the individual complainants. If you so find from the evidence and by its greater weight, you will answer the second issue ‘Yes.’ If you fail to so find, you will answer it ‘No.’ ”

The core of this instruction is lifted bodily out of its context in Kass v. Hedgpeth, 226 N.C. 405, 38 S.E. 2d 164, and is without relevancy to the pleadings, the testimony, and the issues in the instant action. What has already been said respecting the basis of liability in the law of private nuisance makes it obvious that the instruction under scrutiny conveyed to the jury a rather vague and a quite incorrect notion as to the essential elements of a private nuisance. The instruction is not robbed of its prejudicial character by the fact that the court may have given the jury correct instructions on this phase of the case in other parts of the charge. “It is elementary that where there are conflicting instructions with respect to a material matter- — one correct and the other not — a new trial must be granted, as the jurors are not supposed to know which one is *197correct, and we cannot say they did not follow the erroneous instruction.” Hubbard v. R. R., 203 N.C. 675, 166 S.E. 802.

New trial as to the High Penn Oil Company.

Reversed as to the Southern Oil Transportation Company.