al, in which the jury were supposed to know the truth of their own
knowledge, to the modern establishment of facts by testimony brought
before a jury who are bound to give their verdict according to the
evidence. But there was one mode of proof which, after the Norman
Conquest, made a material addition to the substantive law. This was the
proof by writing, which means writing authenticated by seal. Proof by
writing was admitted under Roman influence, but, once admitted, it
acquired the character of being conclusive which belonged to all proof
in early Germanic procedure. Oath, ordeal and battle were all final in
their results. When the process was started there was no room for
discussion. So the sealed writing was final too, and a man could not
deny his own deed. We still say that he cannot, but with modern
refinements. Thus the deed, being allowed as a solemn and probative
document, furnished a means by which a man could bind himself, or rather
effectually declare himself bound, to anything not positively forbidden
by law. Whoever could afford parchment and the services of a clerk might
have the benefit of a "formal contract" in the Roman sense of the term.
At this day the form of deed called a bond or "obligation" is, as it
stands settled after various experiments, extremely artificial; but it
is essentially a solemn admission of liability, though its conclusive
stringency has been relaxed by modern legislation and practice in the
interest of substantial justice. By this means the performance of all
sorts of undertakings, pecuniary and otherwise, could be and was legally
secured. Bonds were well known in the 13th century, and from the 14th
century onwards were freely used for commercial and other purposes; as
for certain limited purposes they still are. The "covenant" of modern
draftsmen is a direct promise made by deed; it occurs mainly as incident
to conveyances of land. The medieval "covenant," _conventio_, was, when
we first hear of it, practically equivalent to a lease, and never became
a common instrument of miscellaneous contracting, though the old books
recognize the possibility of turning it to various uses of which there
are examples; nor had it any sensible influence on the later development
of the law. On the whole, in the old common law one could do a great
deal by deed, but very little without deed. The minor bargains of daily
life, so far as they involved mutual credit, were left to the
jurisdiction of in