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If a contract be so vague in its terms, that its meaning cannot be certainly collected, and the statute of frauds preclude the admissibility of parol evidence to clear up the difficulty; 5 Barn. & Cr. 588; S. C. 12 Eng. Com. L. R. 827; or parol evidence cannot supply the defect, then neither at law, nor in equity, can effect be given to it. 1 Russ. & M. 116; 1 Ch. Pr. 123.

It is a maxim of law, that, that is certain which may be made certain; certum est quod certum reddi potest Co. Litt. 43; for example, when a man sells the oil he has in his store at so much a gallon, although there is uncertainty as to the quantity of oil, yet inasmuch as it can be ascertained, the maxim applies, and the sale is good. Vide generaly, Story, Eq. El. 240 to 256; Mitf. Pl. by Jeremy, 41; Coop. Eq. Pl. 5; Wigr. on Disc. 77.