Gravid Uterus.] A N A T 
later attends every mortal. It makes an earlier attack on 
thole who have, been fubjecled to violent labour, or given 
themfelves up to pleafure, or lived upon unwholelome di¬ 
et ; than on thofe who have followed a moderate way of 
life, and ufed temperance in their diet, or if they have 
removed from a cold to a warm country. If thefe cattfes 
continue their Operation of rendering the matter of the 
body more denfe, of diminishing its irritability, and aug¬ 
menting the quantity of earth, it is not poffible but de- 
crepid old age inull follow. In it the fenfes are almoft 
deltroyed, the natural power of the mufcles is extremely 
weak, the limbs lofe their llrcngth, the feet efpecially are 
not fufficient lor fupporting and directing the body. The 
callous infenfibility of the nerves cannot be incited to per¬ 
form the office of generation; the very inteftines become 
nadtive, and refule to anfwer to the accuftomed folicita- 
tions: by the induration of the cartilages interpofed be¬ 
tween the vertebr;e, the body bends forward ; by the fall¬ 
ing out of the teeth, the jaws but ill fupport the wrinkled 
lips; and laftly, the heart lofes one half of the frequency 
of its puifation, which it had in the infant date. 
Thus, at lad natural death necelfarily follows; but ve¬ 
ry many people are carried of!' before this time by difea- 
fes. Scarcely one in a thoufand exceeds the age of nine¬ 
ty : one or two perhaps may be found in a century that 
live to the age of 150. Man is long-lived when compa¬ 
red with other animals ; he is alio more tender than any 
of them, has loofer flefli, and fofter bones. Among the 
long-lived people, it is not eafy to fey what w r as the caufe 
of that privilege. England feems to excel all other na¬ 
tions in producing old men : and in general the inhabitants 
of temperate climates live longed. The commonalty has 
almod folely afforded thefe rare examples of longevity; 
as indeed, from the more numerous clafs, we might expect 
a greater number of examples. Sobriety ; a moderate and 
not very rich diet; a mildnefs of manners; a mind not 
endowed with very great vivacity, but cheerful, and lit¬ 
tle fubje< 5 t to care; all conduce to long life. Among 
animals, fowls are longer lived than many others, but fiffies 
the mod. of all; the latter have the fmalled heart, and the 
flowed growth, and their bones are never hardened. 
Death happens fometimes, but rarely, from mere old 
age. This we fay happens when the powers, fird of the 
mufcles fubjedl to the will, then of thofe that are fubfer- 
vient to the vital functions, and laftly, of the heart, gra- 
A NATO MY of the 
TO invedigate what happens in the interior parts of a 
female during the production of a new living animal, is 
mdeed a very arduous undertaking. We (hall fird relate 
what experience (hews to be true, and then add the hypo- 
thefes by which the learned have endeavoured to fupply 
what fne does not teach. How few particulars are yet at¬ 
tained, and how difficultly they are attainable, in fb ob- 
feure a fpeculation, mult be obvious to every candid and 
impartial mind. 
To throw the utmod light upon fo delicate a fubje£t, 
we (hall begin v/ith the mod fimple animals, and after¬ 
wards take notice of what nature has added in others whofe 
fabric is more compounded. The fmalled animals, then, 
which have very few or no limbs, the lead didindtion of 
parts, the fhorteft life, and the vital fundtions both few 
and very familiar to one another, bring forth young ones 
like themfelves, with no didindtion of fexes ; all of them 
are fruitful, and none imparts fecundity to the red. Some 
animals exclude their young through a certain cleft of 
their bodies; from others, limbs fall off, which are corp- 
pleted mto animals of a kind fimilar to thofe from which 
they have fallen. This kind of generation is extended 
very wide, and comprehends the greater part of animal 
life. Thofe again, which are a little more compounded, 
STou L Nq, 4 s> 
' O M Y. 6. n 
dually fail; fo that old men ceafe to live through mere 
weaknefs, rather than through the oppreffion of any dif- 
eafe. We have often obferved the fame kind of death in 
brutes. The heart becomes unable- to propel the blood to 
the extremities, the pulfe and heart defert the feet and 
hands; yet the blood continues to be lent from the heart 
into thofe arteries that are next to it, and to be again car¬ 
ried back to it: thus the flame of life is fupported for a 
little while ; but it is loon extinguilhed, for the heart lt- 
felf being totally deprived of its powers, and not irritable 
by the blood to any eftedtual motion, cannot drive the 
blood through the lungs, that the aorta may receive its 
due quantity. The utmoft force of respiration is exerted 
in order to open a paffage to the blood through the lungs, 
until even the powers, given by nature for performing the 
aftion of infpiration, become unequal to their talk, and 
ceafe altogether. The left fide of the heart neither re¬ 
ceives blood, nor is irritated, and therefore remains at reft; 
the right ventricle, and laftly the auricle of the fame fide, 
for a while receive the blood brought by the veins from 
the cold and contracted limbs, and being thus irritated 
they continue to beat weakly. But laftly, when the reft 
of the body has become perfectly cold, and the fat itfelf 
congealed, even this motion ceafes, and death becomes 
complete. 
We would call that death, when the whole irritable na¬ 
ture has left the heart; for the mere relting of the heart 
is not without hope of a revival of motion: neither does, 
the putrefaction of any .part of the animal body demon- 
ftrate the death of the whole animal; nor does its infenfi- 
bility or coldnefs do fo ; but all thefe circumltances joined 
together, and perpetually increaling, with the (tiffnefs 
which follows the coagulation of the fat by reft and 
cold, can only be admitted ligns of death in any doubtful 
cafe. 
The dead body now haftens to putrefaction. Tiie fat, 
water, and gluten, in confequence of reparation and diffo- 
lution, evaporate: the earth, deprived of its bonds of 
union, infenlibly moulders away, and mixes itfelf with 
the dull: the fpirit departs whither God hath deftined it. 
By death it is indeftruCtiblc-; as may be proved by an at¬ 
tention to the following fa£t, that many dying people, 
though their bodily powers are wafted, and their, bodies 
are even decayed, give evident ligns of a ferene, vigorous, 
and happy, mind. 
GRAVID UTERUS. 
all bring forth their young ; yet in fuch a manner, that a 
certain particle peculiar to themfelves is generated in their 
bodies, diflimilar to the whole animal, and contained in 
fome involucra, within which lies the germ that is after¬ 
wards to become fimilar to its parent; this is commonly 
called the ova, or egg. 
Animals that are ftill more complex have both eggs, 
and male femen befides; fo that both fexes are joined in 
the fame individual; and this clafs is the mod numerous. 
The male femen is that aftive fubftance which it is necelfa- 
ry to fprinlde on eggs to render them prolific, although it 
never grows alone into a new animal. In this clafs, there¬ 
fore, a juice is prepared by its own proper organs, which 
is likewife poured on the eggs through organs proper to 
itfelf, but different from the former, in order to genera¬ 
tion. Thofe animals are much more numerous which 
have both a male juice and female eggs; yet cannot fe¬ 
cundate themfelves, but require true coition. For tw® 
animals of this kind mull fo agree in the work of fecunda¬ 
tion, that each impregnates the other with its male organs, 
and again fuffers itfelf to he impregnated in its female 
ones by the male parts of the other. 
Approaching nearer and nearer to man, we eome next 
to that clafs, of which, fome individuals have only male 
s A organs, 
