hewing it at medical lectures.

SIR PATRICK. Still, that wasnt quite what you intended, was it?

RIDGEON. I took my chance of it.

SIR PATRICK. Jane did, you mean.

RIDGEON. Well, it's always the patient who has to take the chance
when an experiment is necessary. And we can find out nothing without
experiment.

SIR PATRICK. What did you find out from Jane's case?

RIDGEON. I found out that the inoculation that ought to cure sometimes
kills.

SIR PATRICK. I could have told you that. Ive tried these modern
inoculations a bit myself. Ive killed people with them; and Ive cured
people with them; but I gave them up because I never could tell which I
was going to do.

RIDGEON [taking a pamphlet from a drawer in the writing-table and
handing it to him] Read that the next time you have an hour to spare;
and youll find out why.

SIR PATRICK [grumbling and fumbling for his spectacles] Oh, bother your
pamphlets. Whats the practice of it? [Looking at the pamphlet] Opsonin?
What the devil is opsonin?

RIDGEON. Opsonin is what you butter the disease germs with to make your
white blood corpuscles eat them. [He sits down again on the couch].

SIR PATRICK. Thats not new. Ive heard this notion that the white
corpuscles--what is it that whats his name?--Metchnikoff--calls them?

RIDGEON. Phagocytes.

SIR PATRICK. Aye, phagocytes: yes, yes, yes. Well, I heard this theory
that the phagocytes eat up the disease germs years ago: long before you
came into fashion. Besides, they dont always eat them.

RIDGEON. They do when you butter them with opsonin.

SIR PATRICK. Gammon.

RIDGEON. No: it's not gammon. What it comes to in practice is this. The
phagocytes wont eat the microbes unless the microbes are nicely buttered
for them. Well, the patient manufactures the butter for himself all
right; but my discovery is that the manufacture of that butter, which
I call opsonin, goes on in the system by ups and downs--Nature being
always rhythmical, you know--and that what the inoculation does is to
stimulate the ups or downs, as the case may be. If we had inoculated
Jane Marsh when her butter factory was on the up-grade, we should have
cured her arm. But we got in on the downgrade and lost her arm for her.
I call the up-grade the positive phase and the down-grade the negative
phase. Everything depends on your inoculating at the right moment.
Inoculate when the patient is in the negative phase and you kill:
inoculate when the patient i