> 
‘and J ecliged forw 
THE AR YT. 
~obferve, that the changes produced in the fituation of the 
heart by its weight only, are very limited, and that when its 
pulfations are é nfible in a very cratic extent, or ina 
different. fituation from what we have defcribed, the caufe 
e fome difeafed affeetion. A diftended ftate of the 
fewack may urge the point of the heart upwards ; and the 
whole organ may afcend, when the gravid uterus or any 
other caufe of *diftenfion affecting the whole abdomen, acts 
on the diaphragm in that direction. When the fluid of 
afcites is doddetity withdrawn, it defcends again, makes 
different angles with the large veffels, and carries the aorta 
down with it. 
nftances have occurred, but rarely, in which'the fituation 
of the heart has been ERE fo that its point extended to 
the ribs of the right fide, and its bafis was towards the left ; 
at the fame time a fimilar unnatural pofition has been ob- 
ferved in all the large veffels, and the abdominal vifcera. 
This cap formation does not affe& the funétions of the 
organs, Ww mit im every refpect as perfeét as in the more 
common arran 
The volume Of the heart, i in fubjects of the fame age, pre- 
fents fuch numerous varieties, that it cannot be determined 
with any exactnefs, Soemmerring fays, that it weet, 
together with the pericardium, from 10 to 20 oun t 
is eenctaly larger in proportion to the body, as a fubjea 
is youn 
he aie of the et) " fomewhat conical, or it re- 
fembles ep tet the fection of a cone, divided by a perpen- 
dicular plane carried Samed it from the bafis to the apex. o 
‘The point is rounded 
ae s of 
and id mufcular and membranous 
ata a Aan 
(facies ma 
othe gs “yea 
pee of it which belong s to the right 
ventric is aot at cpu that belonging to the left, and 
ring a branch 
of the left ert artery. ve correfponds to = 
fuperior margin of the eae retin The inferio 
furface (facies minor or plana) is flat and horizontal, ay 
refts on that part 
ragm. Here the left ventricle occupies a larger {pace 
than the right, and i be not fo flat; the two are feparated b 
ih eager a hates ese pi th 
a er er hnger t is ¥ 
wnwards ; the "ER aor a ti 
hie a thick, and es a wie backwards. 
bafis 
of the wraeee turned ackeartk: upwards, and 
$y and i in contact with each T 
onan 
heart contains four cavities, which ar 
The former coined: Be. 
he 
ventricles nad the auricles. 
of the heart ; 
right and d left. 
right ventricle and auricle are turned towards the front of 
the chelt, while the left cavities are direQed backwards : 
hence the epithets anterior and_potterior ag the fitua- 
tion of thefe organs more correétly tham-right and left, Tn 
the J ly ages of anatomy, when there were no opportuni. 
ties of examining human bodies, the.carcafes of brutes were 
employed for the purpofes of anatomical inveltigation; in 
them the pofiiion of the heart is ftraight inftead of oblique, 
fo that the two fides are right and left in their ir pofition. 
Thefe names have been transferred to human anatomy, 
are now fo firmly eftablifhed in cen ufe, that the more 
correct ones of anterior and pollerior will probably. sot 
fuperfede them 
The auricles communicate with the ventricles by openings, 
of which the fize, form, and itruéture will be deferibed 
hereafter. ‘They receive the blood returned from the ” 
rious parts of the body by the veins: the ventricles exj 
again eke the arteries. "The ri 
or anter 
m) to the 
he right ventricle i dexter, or anterior or p 
monalis ) gives origin to the pulmonary artery ; and the 
ree finilter, pofterior, or aorticus) to the aorta. 
th the auricles and fhe ventricles are fo clofely connected 
xternal appearance, a fingle organ: 
ided on oe infide by a com ge 
The 4 nae and ventricle ye the right half or fide 
of the heart — dextrum) ; and the other cavities the left 
fide (cor fini 
Each bedi and ventricle poffeffes two kinds of openingti 
by thofe of one defcription the auricles receive 
the veins, and thefe are more than one in each cavity 5 ; by ar 
manner, each ventricle has an opening, through ‘which blood 
arrives in its cavity, and another, by which it nape 
De fheudhare of the suricica god ie el 
and this is cally plies by a comparative view 
unctions. their 
ee are urate av Saal ro} 
‘to the right, adh pericardium by means of the fibres, and ihe wh ey a 
aterics which cif from, and of the h sieheitls bed fee be os 
a vifcus. The apex, t Ae oe " on < eek inclu from its origin to its termination, a 
he sell, 18 Ob of whic confiderable length. They are ren 
the ieee while in the atone Bie more, powerful bechiaer jeer eiees 
left is longer than the right. apex is almo: and fo much rss a 
bifid from the meeting of ¢ grooves of the | upper and to be entirely unlike the 
lower furfaces. ‘ Mode inte which che. ves are very at ir a 
» the ant 10) the righ ventileyi thine the right, Ry ara, e blood only through the Jus - 
fhorter t ry , Ww sheen much weaker than the left, which has © ‘ge ee 
y itis meee wae ‘theo diane part ofthe boy 
auricle is nee at fi bafis of the ee i <e 
