The same Law is, where a Feoffment is made of two Acres, the one for Life, the other in Fee, without determining in certain in which he shall have Fee; this in∣certain Feoffment may be reduced to cer∣tainty, as if the Feoffee loose both the Acres by default, he may have a quod ei deforceat for the one, and a Writ of Right for the other Acre, and thereby the certainty of the gift shall be determined and known. Lit. Fo. 13. a.
And so, if one Grant a Rent-charge to one, now the Grantee may avow or have a writ of Annuity, and which of them he will use shall be maintainable, and yet at the Com∣mencement it was incertain, and yet not∣withstanding this incertainty the Grant was good. Lit. Tit. Rents Fo. 13. a.
In like manner, if a man Grant to one 20s. or a Robe yearly, the Grantee there cannot know the certainty of the Grant; for peradventure he shall have alwayes the 20s. or perhaps alwayes the Robe, and yet the Grant there shall be held good, because that it is reducible to a certainty by the Will of the Grantor. 9 E. 4. 37 en Dett. per Lit. Fo. 13. a.
And so, a Lease for so many years as I. S. shall name, is good, and yet it is incertain; but if I. S. name a certain number, then it is good ab initio. Lit. ib.