1821.) The Royal Society of London, 341 
arranged into fibres and bundles, held 
together by the latter. It is pervaded 
by blood-vessels, but the arteries never 
anastomose, and the veins, which are 
very small, are supplied with valves, 
and perform the office of lymphatics, 
carrying the absorbed matter into the 
superior longitudinal sinus. 
That the cortical part of the brain is 
the seat of memory, is an opinion, says 
Sir Everard, which I have long enter¬ 
tained, from finding that any continued 
undue pressure upon the upper anterior 
part of the brain entirely destroys me¬ 
mory, and a less degree materially di¬ 
minishes it. Pressure upon the dura 
mater, where the skull has been tre¬ 
panned, puts a temporary stop to all 
sense, which is restored the moment 
that pressure is removed: and the organ 
appears to receive no injury from re¬ 
peated experiments of this kind hav¬ 
ing been made. In hydrocephalus, 
when the fluid is in large quantity, 
and there only remains the cort ical part 
of the brain and pons Verolii connect¬ 
ing it to the cerebellum, all the func¬ 
tions go on, and the memory can retain 
passages of poetry, so as to say them by 
heart; but a violent shake of the head 
produces instant insensibility. Pressure 
in a slight degree upon the sinciput, pro¬ 
duced in one case complete derange¬ 
ment, with violent excess of the pas¬ 
sion of lust, both of which went off 
upon removing, by the crown of the 
trepan, the depressed bone. 
And adverting to the abundance and 
office of the transparent mucus, Sir Eve¬ 
rard says, 4 * there can be no doubt that 
the communication of sensation and vo¬ 
lition more or less depend upon it.’’ 
Indeed, it is evident that those func¬ 
tions cannot be ascribed to any indivi¬ 
dual component of the brain and 
nerves, but belong to them as entire 
structures. 
The remainder of this part of the 
lecture is taken up in attempting to 
show that the above-mentioned mucus 
exists ready formed in the blood, and 
that it is the medium 44 by which the 
colouring matter is attached to the sur¬ 
face of the red globules,' 51 and that fat 
may exist in the blood. The next por¬ 
tion of this lecture is devoted to the pro¬ 
vision for carrying off the fluids taken 
into the stomach, whenever the quan¬ 
tity or quality interferes with the pro¬ 
cess of digestion. 44 To do this by the 
route of the thoracic duct, was not only 
too circuitous to correspond with the 
general simplicity of the operations of 
nature, but was mixing these hetero¬ 
geneous liquids in too crude a state, 
with the general circulation of theblood. 
That there was some unusual mode of 
conveying fluids from the stomach to 
the urinary bladder, I have upon a for¬ 
mer occasion established, since they ar¬ 
rived there when both the pylorus and 
thoracic duct were tied up, and the 
spleen was removed out of the body; 
but till the fact of valvular vessels sup¬ 
plying the office of absorbents was as¬ 
certained, any opinion respecting the 
route of fluids from the stomach, must 
continue to be entirely hypothetical. 1 ’ 
Sir Everard then demonstrates the 
existence of such vessels, and describes 
their situation and appearance, by en¬ 
gravings of Bauer’s drawings. 
44 To show the course of the absorbed 
fluids, as well as to give a clear idea of 
every thing connected with so impor¬ 
tant a discovery, a drawing of the spleen, 
the vas breve, and cardiac portion of 
the stomach, is annexed, and as the 
trunk of the splenic vein forms one of 
the trunks of the vena portse, the li¬ 
quids are directly carried to the liver, 
forming a part of the materials employ¬ 
ed in producing the bile; the remain¬ 
der only returning by the vena cava to 
the heart. 
44 This additional quantity of liquids 
passing along the splenic vein, accounts 
for its being five times the size of the 
artery, as well as for the blood in that 
vein having a greater proportion of se¬ 
rum than the blood in any other, which 
has been long asserted, and which I 
found by actual experiments to be the 
case; but being unable to account for 
it, as I can now, I was willing to admit 
that the mode of measuring might be 
erroneous.” 
The spleen is then shown to consist 
of blood-vessels, between which there 
is no cellular membrane, the interstices 
being filled with serum, and with the 
colouring matter of the blood from the 
lateral orifice in the veins, when these 
vessels are distended ; which serum is 
afterwards removed by the absorbents 
belonging to the organ, and carried into 
the thoracic duct by a very large 
absorbent trunk; so that from this 
mechanism 44 the spleen appears to be a 
reservoir for the superabundant serum, 
lymph globules, soluble mucus, and 
colouring matter, carried into the cir¬ 
culation immediately after the process 
of digestion is completed.” 
The Bakerian lecture, by Captain 
Henry Kater, is on the best kind of 
steel 
