barely three or four inches long, of about the diameter
of a small quill and of a calibre that will barely admit an ordinary
knitting needle. And yet we speak of it with bated breath. When we
remember that this little, twisted, blind tube opens directly out of one
of the largest pouches of the intestines (the _caecum_), and that it is
easy for anything that may be present in the large pouch--food,
irritating fragments of waste matter, or bacteria--to find its way into
this fatal little trap, but very difficult to find the way out again, we
can form some idea of what a literal death-trap it may become.

How did such a useless and dangerous structure ever come to develop in a
body in which for the most part there is mutual helpfulness, utility,
and perfect smoothness of working through all the great machine? To
attempt to answer this would carry us very far back into ancient
history. But to make such backward search is absolutely the only means
of reaching an answer.

"But," some one will object, "how perfectly irrational, not to say
absurd, to propose to go back hundreds of thousands of years into
ancient history, to account for a disease which has been
discovered--according to some, invented--within the past twenty-five
years!"

Appendicitis is a mark, not a result, of a high grade of civilization.
To have had an operation for it is one of the insignia of modern rank
and culture. Our new biologic aristocracy, the "Appendix-Free," look
down with gentle disdain upon their appendiciferous fellows who still
bear in their bodies this troublesome mark of their lowly origin. In
short, the general impression prevails that appendicitis is a new
disease, a disease which has become common, or perhaps occurred at all,
only within the last quarter of a century, and which therefore--with the
usual flying leap of popular logic--is a serious menace to our future,
if it keeps on increasing in frequency and ferocity at anything like
the same rate which it has apparently shown for the past fifteen years.

As this feeling of apprehension is in many minds quite genuine, it may
be well to say briefly, before proceeding further, first, that, if there
be any disease which absolutely and almost exclusively depends upon
definite peculiarities of structure, it is appendicitis, and that these
structural peculiarities of this tiny, cramped tag of the food-canal
have existed from the earliest infancy of the race. So it is almost
unthinkable tha