I dissent. In my opinion the evidence in this case totally fails to support the trial court’s special finding that the fire was caused by the negligence of defendant Combs in driving the truck into the barn “which contained infiam *136 mable material, to wit: loose hay and straw at which time hot gas and sparks emanated from the exhaust system of the truck, which caused the said hay to ignite. . . . ” 1

No witness was produced who saw the fire start. Although obviously “hot gas” emanates from an exhaust pipe while any internal combustion engine is running, there was no evidence whatever that such gases would cause the hay to ignite or that defendant’s truck gave off sparks from its exhaust system at the time of the fire or at any other time. On the contrary, the only evidence on the subject showed that the vehicle was properly equipped with a muffler, which operated to lower the exhaust pressure, cool the gases, and arrest sparks. Such a muffler has been declared by statute in California (Pub. Resources Code, § 4167) to be an adequate spark arresting device for use on trucks operated on forest, brush, or grass-covered lands even during periods of unusual fire hazard conditions.

A firetruck driver from the State Division of Forestry arrived on the scene within minutes after the blaze was discovered, examined the muffler, and found nothing wrong with it; the same witness observed that the exhaust system was on the left side of the truck whereas defendant had informed him that the fire started on the right side. A representative of Hertz Corporation from whom defendant Combs had rented the truck testified that while the truck was in the same condition as at the fire, the exhaust and muffler system was carefully checked. No leaks were found, and the vehicle could not be made to backfire. Hertz mechanics also tried to ignite a gasoline-soaked rag “by holding it immediately behind the exhaust pipe, the tail pipe, with the motor running at different speeds from idle right through its full r.p.m., and nothing happened.” It would appear to be a matter of common knowledge that a gasoline-soaked rag is at least as combustible as the “dry oat and vetch hay” in plaintiffs’ barn. The Hertz representative further testified that trucks such as that used by Combs are customarily rented by Hertz to the United States Forestry Service each year to fight fires and are used “in the hills when the fire hazard is the greatest. . . . They *137 have never asked us to install any fire prevention other than what is on the trucks, and to my knowledge there is none on their own trucks. ’ ’

There is thus a total absence of evidence to support the court’s specific finding that the hay was ignited by “hot gas and sparks [which] emanated from the exhaust system of the truck.” Nor can the judgment be supported by resort to the doctrine of res ipsa loquitur. As a general rule, res ipsa loquitur applies where the accident is of such a nature that it can be said, in the light of past experience, that it probably was the result of negligence by someone and that the defendant is probably the person who is responsible. (Di Mare v. Cresci (1962) 58 Cal.2d 292, 298-299 [5] [ 23 Cal.Rptr. 772 , 373 P.2d 860 ], and cases there cited.) Although it has been held that if that doctrine is applicable it may be relied upon in support of a jury verdict even though plaintiff offers no instruction on the subject and none is given (see Rogers v. Los Angeles Transit Lines (1955) 45 Cal.2d 414, 418 [3] [ 289 P.2d 226 ] ; Jensen v. Minard (1955) 44 Cal.2d 325, 329 [5, 6] [ 282 P.2d 7 ]; Rose v. Melody Lane (1952) 39 Cal.2d 481, 488 [10] [ 247 P.2d 335 ]), such an approach is obviously not appropriate when as here the trial was by the court without a jury and specific findings were made following request pursuant to the provisions of Code of Civil Procedure section 634. 2 Under such circumstances that section prohibits inferred findings against appellant on the issue in question. (See City of National City v. California Water & Tel. Co. (1962) 204 Cal.App.2d 540, 545 [2, 3] [ 22 Cal.Rptr. 560 ]; Calloway v. Downie (1961) 195 Cal.App.2d 348, 353 [5] [ 15 Cal.Rptr. 747 ]; Kerr Land & Timber Co. v. Emmerson (1965) 233 Cal.App.2d 200, 222 [15-17], 230-231 [33] [ 43 Cal.Rptr. 333 ]; Corrigan v. Stiltz (1965) 233 Cal.App.2d 381, 384 [ 43 Cal.Rptr. 548 ]; Garber v. City of Los Angeles (1964) 226 Cal.App.2d 349, 354-356 [7-9] [ 38 Cal.Rptr. 157 ].) Plaintiffs point out that the court made both a specific and a general finding of negligence. The general finding was merely that the paragraphs of the complaint which charged that defendants negligently maintained and operated the truck and negligently “conducted themselves” *138 on plaintiffs’ premises “are true, except as they are inconsistent with” the specific findings. However, under section 634 it is the specific finding on the negligence issue to which plaintiffs must look in support of the judgment, rather than to general findings touching on the same issue. (City of National City v. California Water & Tel. Co. (1962) supra, 204 Cal. App.2d 540, 545 [2, 3] ; see also San Bernardino Valley Water Dev. Co. v. San Bernardino Valley Mun. Water Dist. (1965) 236 Cal.App.2d 238, 267-268 [ 45 Cal.Rptr. 793 ].) It is worthy of note that although trial briefs submitted by the parties argued the res ipsa loquitur theory in considerable detail the court made no specific finding responsive to that argument, but instead expressly found that the hay had been caused to ignite by “hot gas and sparks” emanating from the truck’s exhaust system. It is therefore unnecessary to determine whether under the circumstances of this ease the res ipsa loquitur doctrine applied and whether findings based on that doctrine would find support in the evidence.

I would reverse the judgment.

Traynor, C. J., and McComb, J., concurred.

This finding was made in response to defendants’ request for special findings “as to how or in what respect or in what manner it is found that defendants were negligent, and as to how or in what manner or in what respect any such negligence was a proximate cause of the fire and damage claimed, and as to what act, omission, conduct or condition is found to have been negligently done, omitted or maintained, and as to what act, omission, conduct or condition is found to have caused the fire and the claimed damages.”

Seetion 634 in pertinent part: “If upon appeal ... it appears that the court has not made findings as to all facts necessary to support the judgment, or that the findings are ambiguous or conflicting upon a material issue of fact, the [appellate] court . . . shall not infer that the trial court found in favor of the prevailing party on such issue if it appears that the [appellant] . . . made a written request for a specific finding on such issue . . . prior to the entry of judgment . . .