PHYSIOLOGY OF THE NERVOUS SYSTEM. 
next paragraph he enquires whether nerves can 
establish any communication or consent with 
each other in their ganglia, and also discusses 
the use of ganglia, giving his assent, in some 
degree, to the doctrine which he assigns to 
Unzer and Winterl,* that external impressions 
are capable of being reflected by ganglia as they 
are reflected in the sensorium commune, and 
that ganglia are particular centres of sensonal 
impressions (sensoria particularia). He sup- 
poses that the action of the heart may be ex- 
plained in this way through the impressions 
made by the blood upon its sensitive nerves 
which are reflected at the ganglia ;+ and he con- 
cludes by admitting it to be probable that besides 
the sensorium commune which resides in the 
medulla oblongata, the medulla spinalis, &c., 
there are sensoria particularia in ganglia and 
anastomoses of nerves (concatenationibus ner- 
vorum) if which external impressions are re- 
flected, without their reaching the sensorium 
commune. f 
In the fifth and last chapter Prochaska dis- 
cusses the animal functions of the nervous 
system. He shows that the soul, ens incor- 
poree prosapie, uses the nervous system as an 
instrument, and that, in all animal functions, it 
is the principium agens et determinans. He 
describes the principal parts into which the 
animal functions can be conveniently resolved, 
as perception, judgment, will, to which may be 
added imagination and memory. For the ex- 
ercise of these he lays down that the joint and 
harmonious action of the mind and brain is 
necessary, and he assigns to each of them a 
-_* Unzer, Gundriss eines Lehrgebaudes von der 
Sinnlichkeit der thierischen Korper, 1768 ; also, 
Ertse Grunde einer Physiologie der eigentlichen 
thierischen Natur thierischer Korper. 1771. Win- 
terl, Inflammationis nova theoria, Viennz, 1767. 
Ihave not had an opportunity of perusing any of 
the works of Unzer. They are, indeed, little known 
in this conntry, having first appeared at a time 
when German literature was scarcely at all culti- 
vated here. The only English medical writer with 
whom I am acquainted, who has made distinct re- 
ference to Unzer from having apparently studied 
his works, is Sir Alexander Crichton, who seems to 
have formed a high estimate of Unzer’s Erste 
Grunde einer Physiol, as I gather from his work on 
Mental Derangement, published in 1798. Dr. Baly, 
the learned translator of Muller’s Physiology, also 
refers to Unzer ; and I must express my obligations 
to an interesting article in Dr. Forbes’s journal (the 
British and Foreign Medical Review) for July, 
1847, which contains a good abstract of Unzer’s 
views, with an account of his writings. From this 
it is plain that Unzer had very enlarged views with 
reference to the phenomena of the nervous system, 
and perfectly appreciated the distinction to be made 
between those actions with which the mind is con- 
cerned either as excitor or recipient, and those 
which in their causation and developement are 
wholly independent of the mind, although not un- 
perceived by it. The publication of Unzer’s prin- 
cipal works and also of Prochaska’s in an English 
dress would be a great boon to the student of the 
physiology of the nervous system, and would most 
fegitianarsty come within the scope of the Sydenham 
Society. 
t This is the doctrine in most favour at the pre- 
sent day. 
¢ Itis plain from the context that Prochaska had 
no idea of these sensoria having any connection with 
the mind, or with the mental power of perception. ° 
721F 
different locality in the brain. In the last see- 
tion he again defines the animal actions, and 
distinguishes them from those which are de- 
pendent on a physical exciting cause; and 
argues against the Stahlian doctrine, which 
placed each movement and function of the body 
under the contro! of the soul. 
These doctrines are repeated and somewhat 
enlarged upon in a much later work by Pro- 
chaska, published at Vienna in 1810, entitled, 
“ Lehrsatze aus der Physiologie des Men- 
schen,” a third and much enlarged edition of 
a text book for his lectures. The whole section 
on the nervous system will repay an attentive 
perusal, and especially the chapter headed 
“ Verrichtung des allgemeinen Sensoriums,” 
which contains a review of the doctrine of re- 
flex actions. A later edition of the same work, 
somewhat compressed in some parts, published 
in 1820, contains a repetition and a distinct 
enunciation of the same doctrines (p. 92).* 
It is not a little remarkable, and at the same 
time highly discreditable to physiologists, that 
views so comprehensive and so striking should 
have been suffered to fall into neglect and to be- 
come almost wholly forgotten, and that the pe- 
culiar power of nervous centres to develope 
motions in response to sensorial impressions, or, 
in Prochaska’s language, “ to reflect sensorial 
into motor impressions,” should have been lost 
sight of. Le Gallois, indeed, had recognized this 
power, and Blane had evidently much insight 
into it; Mayo, likewise, had formed a very 
correct appreciation of it, as shown by his 
observations on the actions of the iris. But 
none of these physiologists were fully impressed 
with its immense importance. It is to Dr. 
Marshall Hall in this country and to Professor 
Miler in Germany that science is most in- 
debted for awakening the attention of physi- 
* Geo. Prochaska was born in 1749, and studied 
medicine at Vienna, where he was clinical assistant 
to the celebrated De Haen. He published an in- 
augural dissertation de wrinis, but the works which 
first attracted notice were his Questiones Physiolo- 
gice, Vienna, 1778; and his treatises De Carne 
Musculari, and De Structura Nervorum. In 1778 
he was made professor of anatomy and of ophthal- 
mic surgery at the University oi Prague, where he 
formed a valuable cabinet of preparations of mor- 
bid parts. In 1791] he was translated to a similar 
chair in the University of Vienna, with the title of 
Lehrer der hohern Anatomie, Physiologie, und 
Augenarzneykunde. M. Dezeimeris, from whose 
Dictionnaire Historique de la Médecine (art. Pro- 
chaska) this acconnt is abridged, remarks of him 
that ‘‘ he was one of those who strove to reduce 
the laws of life to the general laws of nature, and 
to make physiology a branch of experimental phy- 
sics.” Prochaska died on the 17th of July, 1820. 
The works in which he propounded his views re- 
specting the nervous system are, 1. Annotation. 
Academic. fasc. iii., Prague, 1784. 2. Lehrsiatze 
aus der Physiol. des Menschen, Ist ed., 1797, in 
2 vol.; 2nd ed. 1802; 3rd ed. 1810. 3. Opera 
minora Physiologici et Pathologici Argumenti, 
p-i.etii. 4, Physiologie oder Lehre von der Na- 
tur des Menschen, 1820. To these, perhaps, may 
be added a Latin edition of his Physiology, Insti- 
tutiones Physiologie Humane, 1805-6; and Disq. 
Anatom. Phys. Organismi Corporis Humani, ejusq. 
Processus Vitalis, 1812; but neither of these works 
have I seen. 
