DIA 
Aion of the Diaphragm. 
When this mufcle contraGs, the ey of its fibres is 
deftroyed ; inftead of curved, they now defcribe ftraight 
line cS 5 and the {pace which is thus gained in the cheft, is 
ie in the le “ne contraGion of the crura draws 
t of the tendinous centre, which can de- 
e the anterior parictes of 
te cavity are puthed forwards by the impulfe communicated 
to the vitcera. If the abdominal mnfcles, inttead of yiclding, 
ntraét upon the vilcera, the effects of the dia aphragm’s ac- 
‘io are particularly felt about the pelvis, as in expellt ing the 
urine, foeces, and child in the = of parturition. The 
chet is enlarged by the dia aphragm n the aga adap di- 
reGtion, and alfo laterally at its fame part. 
gently, the middle aa conneGted with the ee sin 
docs not defcend much; yet it does defcend, as any perfon 
may cafily afcertain by feeling the pulfation of the heart, 
and then 18 poy ease the pag midnifeth- 
ly changes 
Be. 
wing 
its fituation ming low In more 
forcible contractions, this par dead: cities and Haller 
fpeaks of its beco 
lower a inwards. 
ion has no effe&t upon the aorta, as the fides of the 
el paffes, are unyielding, 
and incapable, os their Sth cere of change in diameter, 
Neither is the return of t to the heart through & eer 
inferior vena cava affcCted, as te opening is pla nous 
- fibres draw from all fides. 
O prevent unpleafant 
muf{cle has relaxed, the abdominal 
mufcles, by*their aétion, replace the vifcera, and reftore the 
sai alate to its former co 
se a 2 
r further remarks on this fubje&, fee Respiration. 
For v views of the diaphragm, confult Albinus, Haller «* No- 
va Icon Septi Tranfverfi.”” 3 
o the defcrip- 
ofe a Soemmeaiag and 
Bichat ia their fyftems of aay. 
14PHRAGM is ufed for the feptum fcroti. See Scre- 
1 i is faay es name, given to all parti- 
ca 4 or two parts of a thing; as 
feopen little aa ae in the tubes of long tele- 
ecyce 
DIA 
cela leataey eee an epithet applied to parts hee 
longing to the diaphragm: thus, there are the diaphragma- 
tic ahve ere &e. tt has the fame meaning as the 
term pRren 
DIAPHRAGMITIS, in Medicine, the nofolozical ternr 
for an inflammation of the diaphragm, cr rather of that part 
of the pleura, or lin‘ng qecbie ane of the cheft, which is 
{pread upon the diaphragm 
The membranous and mufcular curtain which feparates 
the lower vifcera from thofe of the brealt, being called by 
the ancients diaphragma and phrenes, the iwfam imation of it 
ations. Hippocrates, Af sinetay 
&c. mention the difeafe under the term pbhrenitis ; intimatin 
at the fame time ae ne are other kinds of the difeafe, 
o be treated like a peripneumony. 
but that the firft i 
But to diftinguifh Ras ‘fon the proper phrenfy, alfo called: 
phrenitis, confifting of inflammaticn of the brain, Boerhaave, 
and others, hele called the difeafe in queftion ponaporeiis r- 
and Sauvages has given it a place in his Nofology, under the 
title ce ae See Van ai hicaaai ad. § 907. 
Sauvage Nofol. uae clafs 3 
13 i a has eae bee deferibed by writers. 
n 
nr 
oerhaave enue 
feestee its fymptoms: * A paraphrenitis is known by ar 
acute continual fever, with an ardent or inflammatory pain of 
the affe€ied part of the gee which, in confequence 
of its nervous membranes, can 
18 a increafed by infpiration, Ae ee one fill 
ing the f 
donic or convulfive ae: 3 a ccnvulfion, a raving, and a 
gangrene”? Aphorifm gog. 
ow it is acknowledged by all the writers, that this difeafe 
diaphra 
en a and fe es ought only be confidered as a variety 
of the latter. &, if the mufcular part of the dia- 
phragm is ever affe&ted with acute inflammation, it is at leaft 
an extremely rare occurrence, and morbid anatomifts have 
not pointed out its ex: oo as raul with any peculiar. 
fet of previous fymptor But the pleura is frequently 
found to have fuffered in (eaniea ener has not extend. 
ed to ae mufcular fubitance, contiguous to it underneath; 
In thefe cafes Dr. Cullen maintains, and we believe he is. 
fully f{upported by the experience of others,, that the fymp- 
toms do not ed from thofe of pleurify; he affirms that in, 
his long pra er witneffed the occurrence of the 
fardonic ae Gane with pleuritic fymptoms ; and that 
8 
high degree of ‘fever, and of the diisgiie 
diathefis accompanying them, than upon the particular part of” 
the membrane, which is infamed. The moft important cone 
fideration, however, is, that it 1s agreed by. thofe who have 
given the moft oppofite opinions. of the peculiarities of the 
difeafe, that it caey a treat = like the various forms of 
an Swieten, loc. cit. Cul 
- 2. note. 
HTHORA, “from Baap a battle i is ufed 
y Galen and Boerhaave, to det ruption of the 
lca inthe ftomach, and by ae for the core 
suption of the foetus in the womb, and abortion. 
DIAPNOICA, 
