channels are crowded by swarms of the red and white hurrying to the
scene. The major part of the activity of the red cells can be accounted
for by the mechanism of the heart and blood-vessels. They are simply
thrown there by the handful and the shovelful, as it were, like so many
pebbles or bits of chalk.

But the behavior of the white cells goes far beyond this. We are almost
tempted to endow them with volition, though they are of course drawn or
driven by chemical and physical attractions, like iron-filings by a
magnet, or an acid by a base. Not only do all those normally circulating
in the blood flowing through the injured part promptly stop and begin to
scatter themselves through the underbrush and attack the foe at close
quarters, but, as has been shown by Cabot's studies in leucocytosis, the
moment that the red flag of fever is hoisted, or the inflammation alarm
is sounded, the leucocytes come rushing out from their feeding-grounds
in the tissue-interspaces, in the lymph-channels, in the great serous
cavities, and pour themselves into the blood-stream, like minute-men
leaving the plough and thronging the highways leading towards the
frontier fortress which has been attacked. Arrived at the spot, if there
be little of the pomp and pageantry of war in their movements, their
practical devotion and heroism are simply unsurpassed anywhere, even in
song and story. They never think of waiting for reinforcements or for
orders from headquarters. They know only one thing, and that is to
fight; and when the body has brought them to the spot, it has done all
that is needed, like the Turkish Government when once it has got its
sturdy peasantry upon the battlefield: they have not even the sense to
retreat. And whether they be present in tens, or in scores, or in
millions, each one hurls himself upon the toxin or bacillus which stands
directly in front of him. If he can destroy the bacillus and survive, so
much the better; but if not, he will simply overwhelm him by the weight
of his body-mass, and be swept on through the blood-stream into the
great body-sewers, with the still living bacillus literally buried in
his dead body. Like Arnold Winkelried, he will make his body a sheath
for a score of the enemy's spears, so that his fellows can rush in
through the gap that he has made. And it makes no difference whatever if
the first ten or hundred or thousand are instantly mowed down by the
bacillus or its deadly toxins, the rear ra