OcTOBER 22, 1897. ] 
tain extent, the doubts held by some as to 
the validity of the conclusion that the 
symptoms witnessed were really and simply 
due to the absence of the organ removed. 
The observer who removes the pancreas 
has to deal with a tangible and measurable 
result, the appearance of sugar in the urine. 
About this there can be no mistake, no un- 
certainty. And the confidence thus en- 
gendered in the conclusion that the pan- 
creas, besides secreting the pancreatic juice, 
effects some notable change in the blood 
passing through it, spread to the analogous 
conclusions concerning the thyroid and the 
suprarenal, and moreover suggested further 
experimental inquiry. By those inquiries 
all previous doubts have been removed ; it 
is not now a question whether or no the 
thyroid carries on a so-called internal secre- 
tion ; the problem is reduced to finding out 
what it exactly does and how exactly it 
does it. Moreover, no one can at the pres- 
ent day suppose that this feature of inter- 
nal secretion is confined to the thyroid, the 
suprarenal and the pancreas; it needs no 
spirit of prophecy to foretell that the com- 
ing years will add to physiological science 
a large and long chapter, the first marked 
distinctive verses of which belong to the 
dozen years which have just passed away. 
The above three lines of advance are of 
themselves enough to justify a certain pride 
on the part of the physiologist as to the 
share which his science is taking in the 
forward movements of the time. And yet 
I venture to think that each and all of these 
is wholly overshadowed by researches of 
another kind, through which knowledge has 
made, during the past dozen years or so, a 
bound so momentous and so far-reaching 
that all other results gathered in during the 
time seem to shrink into relative insignifi- 
cance. 
It was a little before my period, in the 
year 1879, that Golgi published his modest 
note, ‘Un nuovo processo di technica mi- 
SCIENCE. 
609 
croscopia.”* That was the breaking out 
from the rocks of a little stream which has 
since swollen into a great flood. It is 
quite true that long before a new era in our 
knowledge of the central nervous system 
had been opened up by the works of Fer- 
rier and of Fritch and Hitzig. Between 
1870 and 1880 progress in this branch of 
physiology had been continued and rapid. 
Yet that progress had left much to be de- 
sired. On the one hand, the experimental 
inquiries, even when they were carried out 
with the safeguard of an adequate psychical 
analysis of the phenomena which presented 
themselves, and this was not always the 
case, sounded a very uncertain note, at 
least when they dealt with other than 
simply motor effects. They were, more- 
over, not unfrequently in discord with 
clinical experience. In general the con- 
clusions which were arrived at through 
them, save such as were based on the pro- 
duction of easily recognized and often 
measurable movements, were regarded by 
many as conclusions of the kind which 
could not be ignored, which demanded re- 
spectful attention, and yet which failed to 
carry conviction. It seemed to be risking 
too much to trust too implicitly to the 
apparent teaching of the results arrived at ; 
something appeared wanting to give these 
their full validity, to explain their full and 
certain meaning by showing their connec- 
tion with what was known in other ways 
and by other methods. On the other hand, 
during nearly all this time, in spite of the 
valuable results acquired by the continually 
improving histological technique, by the 
degeneration method and by the develop- 
mental method, by the study of the periods 
of myelination, most of us, at all events, 
were sitting down, as our forefathers had 
done, before the intricate maze of encephalic 
structure, fascinated by its complexity, but 
*Rendiconti del reale Istitulo Lombardo, Vol. XII., p. 
206. 
