In severe cases of rheumatism the heart may be attacked within the first
few days of the disease, but usually it is not involved until after the
trouble in the joints has begun to subside; and no patient should be
considered safe from this danger until at least six weeks have elapsed
from the beginning of the fever. The few cases (not to exceed one or two
per cent) of rheumatic fever which go rapidly on to a fatal termination,
usually die from this inflammation of the heart, technically known as
endocarditis. The best way of preventing this serious complication and
of keeping it within moderate limits, if it occurs, is absolute rest in
bed, until the danger period is completely passed.

Now comes another redeeming feature of this troublesome disease, and
that is the comparatively small permanent effects which it produces upon
the joints in the way of crippling, or even stiffening. To gaze upon a
rheumatic knee-joint, for instance, in the height of the
attack,--swollen to the size of a hornet's nest, hot, red, throbbing
with agony, and looking as if it were on the point of bursting,--one
would almost despair of saving the joint, and the best one would feel
entitled to expect would be a roughening of its surfaces and a permanent
stiffening of its movements.

On the contrary, when once the fury of the attack has passed its climax,
especially if another joint should become involved, the whole picture
changes as if by magic. The pain fades away to one-fifth of its former
intensity within twenty-four, or even within twelve hours; three-fourths
of the swelling follows suit in forty-eight hours; and within three or
four days' time the patient is moving the joint with comparative ease
and comfort. After he gets up at the end of his six weeks, the knee,
though still weak and stiff and sore, within a few weeks' time "limbers
up" completely, and usually becomes practically as good as ever. In
short, the violence and swiftness of the onset are only matched by the
rapidity and completeness of the retreat. It would probably be safe to
say that not more than one joint in fifty, attacked by rheumatism, is
left in any way permanently the worse.

But, alas! to counterbalance this mercifulness in the matter of
permanent damage, unlike most other infections, one attack of rheumatic
fever, so far from protecting against another, renders both the
individual and the joint more liable to other attacks. The historic
motto of the British in t