see if any marks
of blood were upon them; to furnish exchange of clothes, or new
disguise, if necessary; to tell him through what streets he could safely
retreat, or whether he could deposit the club in the place designed; or
it might be without any distinct object, but merely to afford that
encouragement which would proceed from Richard Crowninshield's
consciousness that he was near. It is of no consequence whether, in your
opinion, the place was well chosen or not, to afford aid; if it was so
chosen, if it was by appointment that he was there, it is enough.
Suppose Richard Crowninshield, when applied to to commit the murder, had
said, "I won't do it unless there can be some one near by to favor my
escape; I won't go unless you will stay in Brown Street." Upon the
gentleman's argument, he would not be an aider and abettor in the
murder, because the place was not well chosen; though it is apparent
that the being in the place chosen was a condition, without which the
murder would never have happened.

You are to consider the defendant as one in the league, in the
combination to commit the murder. If he was there by appointment with
the perpetrator, he is an abettor. The concurrence of the perpetrator in
his being there is proved by the previous evidence of the conspiracy. If
Richard Crowninshield, for any purpose whatsoever, made it a condition
of the agreement, that Frank Knapp should stand as backer, then Frank
Knapp was an aider and abettor; no matter what the aid was, or what sort
it was, or degree, be it ever so little; even if it were to judge of the
hour when it was best to go, or to see when the lights were
extinguished, or to give an alarm if any one approached. Who better
calculated to judge of these things than the murderer himself? and if he
so determined them, that is sufficient.

Now as to the facts. Frank Knapp knew that the murder was that night to
be committed; he was one of the conspirators, he knew the object, he
knew the time. He had that day been to Wenham to see Joseph, and
probably to Danvers to see Richard Crowninshield, for he kept his
motions secret. He had that day hired a horse and chaise of Osborn, and
attempted to conceal the purpose for which it was used; he had
intentionally left the _place_ and the _price_ blank on Osborn's books.
He went to Wenham by the way of Danvers; he had been told the week
before to hasten Dick; he had seen the Crowninshields several times
within a few days; he h