, 8 O B S E R V A T I O N S O N T H E
3. In fillies, and particularly in the fkate, I have injeaed wax, coloured
with vermilion, from a lymphatic trunk, into fo many fmall branches on
the pia mater of the brain, the membranes of the eyes, and organ of hearing,
that thofe parts were made quite red, and yet there was not a drop of
the injeaion in the arteries or in the red veins.
4. If, to thefe arguments, we add, that the lymphatic glands of our
head and neck are larger and more numerous than, comparing them with
the axillary and inguinal glands, we can fuppofc to correfpond with the
outer fide only of the head, and that they are difpofed in a chain, the top
of which is at the bafe of the cranium, it cannot be doubted, that future
attention to thofe difeafes, in which acrid matter is colleaed within the cranium,
or that proper experiments, made on living quadrupeds, with coloured
or ftrong fcented fubftances poured into the cavity of the cranium, or
accurate difieaion, after tying up the lymphatics in the neck, will fully eftablilli
the proof, that abforption within the head is in all animals performed,
as clfewhere, by the lymphatic fyftem.
E T. 11.
ONE other curious point of Phyfiology, conneaed with the above, remains
to be determined, to wit, What becomes of the lluid which the infundibulum
conveys to the upper furface of the Gianduia Pituitaria? for
that the infundibulum in man and quadrupeds is not a folid imperforated
body, as feveral eminent authors contend*, but is a hollow membranous
tube.
• Viouffens, Neur. Lib. i. cap. 6. De Infundibulo, I
extenfioneni fuam, donatum appareat.
. Nec id fenfili meatu, fecundum totam
Lieutaod, Anat. Hill. Lib. 5. p. 34>. La tige q«i s'cle.e de la glande pituitaire n'a point de ca.itf,
:om:iie on le pretend. Anat. Prat. p. 627.
Petit, Ed. de 1' Anat . par Palfin, Tab. 2. p. 361. L'Entonnoir, • Jc Ms du fentiment, de M. Lieu-
' tand.'
N E R V O U S S Y S T E M . 19
tube, painted with many veffels, I am well aíTurcd by repeated experiments
•*.
In man and in the ox, I have repeatedly injeaed quick filver, or fpirit of
turpentine, coloured with vermilion, from the third ventricle, into the infundibulum,
or I have put the pipe into the infundibulum, and tied it in
with a thread.
In two fuch experiments on an ox, a number of fmall veflels in the fubftance
of the glandula pituitaria were injeaed ; but then I had pulhed the injeaion
with fo mucli force that the infundibulum buril. In all my other
e.xperiments, tlie injeaion did not penetrate that gland, nor did it enter the
veins or fniufes of the fella turcica, nor the valvular lymphatic veflels. I
therefore fufpeaed, that, in the two feemingly fuccefsful experiments, the
injeaion had filled veflels which naturally are not continued from the infundibulum,
but that, after the vefl'els on the coats of the infundibulum
were lacerated, it had got into them, an event that often happens, and has
given occafion to many millakes. Upon the whole, however, confidcring
that all the ventricles of the brain communicate with each other; that the
infundibulum is a hollow tube, conneaing thofe cavities to the glandula
pituitaria-, that this gland, efpecially in an ox, refembles very much, in
colour and confiftence, the lymphatic glands; that the lymphatic veffels,
when they reach their proper glands, divide within them into exceedingly
minute
Haller, El. Phyf. Lib. lo. S. I. p. 58. ' Num cavuin fit infundibulum dubitari poteil.'
S. Th. SoemmerinB de Baf. Enc. el Orig. Net». 1778, after many argument! and experiments,
concludes concerning the infundibulum as follows: Sed haec de infundibulo fuiiciam. Quibus omnibus,
abfque partiom Iludió, rite mecum perpenf.s, nonpotuinon ampleffi .irorum illorum fenten.
tiam, qui infundibulum, f. non perfeae folidum, certe non conTpicuo, oti veteres opiitati funt, canali
perforatum elfe cenfuerint; Lib. 2. § 2. p. 60.
• See the cavity of the infundibulum delineated in the human fubjea, Tab. U. at the letters U. V.
And Tab. V. K. In the Iheep, Tab. IX. Fig. 2. II. Aitd in tile ox. Tab. IX. Fig. 9.