“But if the party whose deed is to be attested is, by disease or other circumstances, rendered unable to see and hear in the usual manner, or can only do so in part, or with difficulty, and, in short, must trust to the fidelity of others, it is plain, both in reason and in law, that some further precautions are necessary. It ought to appear from evidence, that the deed was his own voluntary deed, and sufficiently understood, that instructions were given to make it out in these terms, and that there was no deception, but everything explained and known to the party and all present.
“The Court reduce the whole deeds under challenge.”—President Campbell's Session Papers, vol. 67.