allowed to become the cause of an endless series of terrible effects,
which go down into the distance of the future, multiplying themselves
a thousandfold.

The doctor told Nan many curious things as they drove about together:
certain traits of certain families, and how the Dyers were of strong
constitution, and lived to a great age in spite of severe illnesses
and accidents and all manner of unfavorable conditions; while the
Dunnells, who looked a great deal stronger, were sensitive, and
deficient in vitality, so that an apparently slight attack of disease
quickly proved fatal. And so Nan knew that one thing to be considered
was the family, and another the individual variation, and she began
to recognize the people who might be treated fearlessly, because they
were safe to form a league with against any ailment, being responsive
to medicines, and straightforward in their departure from or return to
a state of health; others being treacherous and hard to control; full
of surprises, and baffling a doctor with their feints and follies of
symptoms; while all the time Death himself was making ready for a
last, fatal siege; these all being the representatives of types which
might be found everywhere. Often Dr. Leslie would be found eagerly
praising some useful old-fashioned drugs which had been foolishly
neglected by those who liked to experiment with newer remedies and be
"up with the times," as they called their not very intelligent
dependence upon the treatment in vogue at the moment among the younger
men of certain cliques, to some of whom the brilliant operation was
more important than its damaging result. There was, even in those
days, a haphazard way of doctoring, in which the health of the patient
was secondary to the promotion of new theories, and the young scholar
who could write a puzzlingly technical paper too often outranked the
old practitioner who conquered some malignant disorder single-handed,