Lewis (P) decided to convert his power equipment to hydraulic equipment. He purchased a hydraulic system in May 1963. P requested from Frank Rowe, a local Mobil oil dealer, the proper hydraulic fluid to operate his machinery. The prior owner of the hydraulic system had used Pacemaker oil supplied by Cities Service, but P had been a customer of D's for many years and desired to continue with D. The only information given to Rowe by Lewis was that the machinery was operated by a gear-type pump; Rowe did not request any further information. Rowe contacted a D representative for a recommendation and sold Pa product known as Ambrex 810. This is a straight mineral oil with no chemical additives. Within a few days, P began experiencing difficulty. The oil changed color, foamed over, and got hot. The oil was changed a number of times. Approximately six months after operations with the equipment had begun, the system broke down, and a completely new system was installed. From April 1965 until April 1967, six new pumps were required during this period, as they continually broke down. P changed the brand of pump from a Commercial to a Tyrone pump. The Tyrone pump used a disposable filter element. Ambrex 810 oil was also recommended by Mobil and used with this pump, which completely broke down three weeks later. P was visited for the first time by a representative of D, as well as a representative of the Tyrone pump manufacturer. The system was completely flushed and cleaned, a new Tyrone pump installed, and a new oil was used which contained a 'defoamant.' P's system worked satisfactorily up until the time of trial, some two and one-half years later. P sued D. D contends that there was no warranty of fitness, that the breakdowns were caused not by the oil but by improper filtration, and that in any event there can be no recovery of loss of profits in this case. On appeal, D maintains that there was no warranty of fitness and that at most there was only a warranty of merchantability and that there was no proof of breach of this warranty since there was no proof that Ambrex 810 is unfit for use in hydraulic systems generally.