MUSCULAR MOTION. 
_ 6piral thread of areolar tissue investing the 
fibre, and Mr. Skey* describes them as an 
external structure, independent of the fibrille, 
which he believes to be arranged in band-like 
Sets around a glutinous substance in the axis 
of the fibre. Ficinust falls into the old error 
of Prochaska, of imagining the striz to be the 
_ tesult of minute flexures of the fibrille, and, 
_ ke him, he confounds with them the secondary 
_ flexures of the whole fibre. Hence, says he, 
_ the appearance of globules or particles is false, 
and only exists during contraction. Other 
“opinions still I have had occasion to allude to 
‘in the course of the article Musctr, which, as 
_ before remarked, is founded on observations 
which have been now two years before the 
public.t 
All the best observers are agreed as to the 
existence of certain appearances, and the dis- 
‘repancies we encounter in the interpretation 
them ought not to bring discredit on all 
arches of this sort. They place, indeed, 
}a strong lizht the difficulty of the inquiry, 
and the necessity for repeated, varied, and un- 
biassed observation, with the best instruments 
“We can command But we are too familiar 
With conflicting and even opposite statements 
concerning visible facts, occurring daily under 
eyes of every one, to suppose it possible 
any kind of investigation wi!l ever be free 
om those causes of error, which lie in man’s 
ature, in his own microcosm, and the effects of 
ich can only be neutralized by the common 
consent of numerous Gndepebdent observers. 
As for those difficulties, whatever they may be, 
ch are inherent in the nature of the subject, 
cannot doubt that they will be, in due time, 
ppreciated and overcome. 
ome of the opinions concerning the nature 
contraction. entertained by the earlier ob- 
ervers, have been already mentioned; another, 
ich seems to have been grafted on the doc- 
trine of the vital spirits, was, that these spirits 
were directed into the fibres and distended 
em, thus causing them to tumify and shorten. 
Accordingly, some (as Robert Hooke and 
wper) considered each fibre or fibrilla to be 
hollow; which need not excite surprise, when 
e find the great Mascagni§ believing each to 
a lymphatic vessel. The first hint of another 
noted hypothesis is to be found in the 
Memoirs of the French Academy. 1724:— 
L’Abbé de Moheres there says,|| “ Les fibres 
? pues qui s’étendent selon la longueur du 
muscle, et dont le raccourcissement fait son 
action, se divisent en un grand nombre de 
tes fibres de méme nature longitudinales 
- aussi, et qui sont liées les unes aux autres par 
des filets nerveux transversaux disposés le long 
des fibres de distance en distance. De plus, 
____ Hes petites fibres charnues ne sont pas droites, 
Mais pli¢es en zigszags, dont les angles se 
* Phil. Trans. 1837. 
t De Fibre Muscularis Forma et Structura. Lip- 
5 4 
t Phil. Trans. 1840, 
Prodromo della grande Anatomia—da Franc. 
Automarchi, Firenze, 1819. 
|| Malgaigne, Anat. Chirurgicale, vol. i. p. 102. 
‘aris, 
-¥OL. 111. 
= 
529 
trouvent aux endroits, ot sont les filets trans- 
versaux.” Hules* examined the abdominal 
muscles of small living frogs, and saw them 
thrown into zigzags during contraction, as he 
imagined ; but he inistook the uncontracted for 
contracted fibres, as I have explained.t Pre- 
vost and Dumas, at a later period,t described 
the same zigzag flexure of the fibres during 
contraction, and further imagined it to be an 
electrical effect produced by the passage of the 
nerves across them at their angles of flexure. 
This doctrine was too captivating not to obtain 
very general credence, especially as it seemed 
to fall in with a notion, at that time very cur- 
rent among speculative physiologists, that the 
nervous influence is a form of electricity. But 
its validity has of late begun to be questioned ; 
Professor Owen,§ in small filariz and in a spe- 
cies of vesicularia, observed a fact opposed to 
it, viz. the bulging of the (unstriped) fibres near 
their centre, without their falling out of the 
Straight line, in contraction. A similar fact 
was observed in the case of the (unstriped) 
muscles of the Polypifera, by Dr. A. Farre;|| 
and Dr. Allen Thomson,{[ on repeating the 
experiment of Hales and Prevost on the Frog, 
“ observed single fibres continuing in contrac- 
tion, and being simp'y shortened, and not fall- 
ing into zigzag plice ; and he was led to sus- 
pect, from this and other circumstances, that 
the zigzag arrangement was not produced until 
after the act of contraction had ceased.” M. 
Lauth, after a careful investigation, concludes** 
that a fibre may shorten with or without zigzag 
inflection. Such, I believe, was the state of 
this question in 1840, when I published the 
observations,t+ on part of which the account 
of the nature of contraction, given in the pre- 
sent article, is principally based. In the fol- 
lowing year I addedf{t a note, on the appear- 
ances met with in human muscle ruptured by 
tetanic spasm, and which seemed to me to 
prove that the conclusions I had previously 
drawn from the phenomena of the rigor mortis 
were true as regards the act of contraction, as 
it occurs in the living body. 
BIBLIOGRAPHY.— To the following works may be 
added the several systematic treatises on descriptive 
anatomy, and on general anatomy and physiology. 
Hooke, Posth. Works, by Waller, 1707. Experi- 
ments and Observations of Robert Hooke, &c. by 
W. Derham, 1726. Malpighi, De Bombycibus, 
. 9, 10. Leeuwenhoek, Phil. Transact. 1674, 
677, 1683, &c. Epist. Physiolog. passim. De 
Heide, Experimenta circa sanguinis missionem, 
fibras motrices, urticam marinam, &c. Amstelod. 
1686 and 1698. Croone, De ratione motis mus- 
culorum, Lond. 1664. Muys, An account of se- 
veral observations concerning the frame and tex- 
ture of the muscles, Phil. Trans. 1714. De car- 
* Hemastatics, R; 59. 
¢ Phil. Trans. 1840. 
¢ Majendie’s Journal, 1825. : 
§ Hunter’s Works by Palmer, vol. iv. p. 261—2, 
note. 
Ht Phil. Trans. 1838, pp. 394 and 396. 
Quoted by Owen, loc. citat. i ‘ ‘ 
** L’Institut. No. 73, quoted by Miiller in his 
Physiology, Baly’s Transl., p. 888. 
tt Phil. Trans. 1840, pt. ii. 
tt Phil. Trans. 1841, pt. ii. . 
M 
