bject in what I have now written and am going to write, is to
impress upon medical students the value of power and promptitude in
combination, for their professional purposes; the uses to them of
nearness of the {Nous}, and of happy guessing; and how you may see the
sense, and neatness, and pith of that excellent thinker, as well as best
of all story-tellers, Miss Austen, when she says in _Emma_, "Depend upon
it, a lucky guess is never merely luck, there is always some talent in
it." Talent here denoting intelligence and will in action. In all
sciences except those called exact, this happy guessing plays a large
part, and in none more than in medicine, which is truly a tentative art,
founded upon likelihood, and is therefore what we call contingent.
Instead of this view of the healing art discouraging us from making our
ultimate principles as precise, as we should make our observations, it
should urge us the more to this; for, depend upon it, that guess as we
may often have to do, he will guess best, most happily for himself and
his patient, who has the greatest amount of true knowledge, and the most
serviceable amount of what we may call mental cash, ready money, and
ready weapons.

We must not only have wisdom, which is knowledge assimilated and made
our own, but we must, as the Lancashire men say and do, _have wit to use
it_. We may carry a nugget of gold in our pocket, or a L100 bank-note,
but unless we can get it _changed_, it is of little use, and we must
moreover have the coin of the country we are in. This want of presence
of mind, and having your wits about you, is as fatal to a surgeon as to
a general.

That wise little man, Dr. Henry Marshall, little in body but not little
in mind, in brain, and in worth, used to give an instance of this. A
young, well-educated surgeon, attached to a regiment quartered at
Musselburgh, went out professionally with two officers who were in
search of "satisfaction." One fell shot in the thigh, and in half an
hour after he was found dead, the surgeon kneeling pale and grim over
him, with his two thumbs sunk in his thigh _below_ the wound, the grass
steeped in blood. If he had put them two inches higher, or extemporized
a tourniquet with his sash and the pistol's ramrod and a stone, he might
have saved his friend's life and his own--for he shot himself that
night.

Here is another. Robbie Watson, whom I now see walking mildly about the
streets--having taken to coal--was driver