did deſcend from king Edward the ſixth to queen Mary, and from her to queen Elizabeth, who were reſpectively of the half blood to each other. For, the royal pedigree being always a matter of ſufficient notoriety, there is no occaſion to call in the aid of this preſumptive rule of evidence, to render probable the deſcent from the royal ſtock; which was formerly king William the Norman, and is now (by act of parliament[1]) the princeſs Sophia of Hanover. Hence alſo it is, that in eſtates-tail, where the pedigree from the firſt donee muſt be ſtrictly proved, half blood is no impediment to the deſcent[2]: becauſe, when the lineage is clearly made out, there is no need of this auxiliary proof. How far it might be deſirable for the legiſlature to give relief, by amending the law of deſcents in this ſingle inſtance, and ordaining that the half blood might inherit, where the eſtate notoriouſly deſcended from it's own proper anceſtor, but not otherwiſe; or how far a private inconvenience ſhould be ſubmitted to, rather than a long eſtabliſhed rule ſhould be ſhaken; it is not for me to determine.
The rule then, together with it's illuſtration, amounts to this: that, in order to keep the eſtate of John Stiles as nearly as poſſible in the line of his purchaſing anceſtor, it muſt deſcend to the iſſue of the neareſt couple of anceſtors that have left deſcendants behind them; becauſe the deſcendants of one anceſtor only are not ſo likely to be in the line of that purchaſing anceſtor, as thoſe who are deſcended from two.
But here another difficulty ariſes. In the ſecond, third, fourth, and every ſuperior degree, every man has many couples of anceſtors, increaſing according to the diſtance in a geometrical progreſſion upwards[3], the deſcendants of all which reſpective couples are (repreſentatively) related to him in the ſame degree. Thus in the ſecond degree, the iſſue of George and Cecilia Stiles and of Andrew and Eſther Baker, the two grandſires and grand-
