<4$ A N A ‘ 
grown in 8 curve direTioru and completely mdofcd the 
ball, The bony juice likewife is changed i f<;r in fome 
cafes the bones grow foft, in others they {well out in bony 
tumours; even cicatrices themfelves have a manifeft 
growth, otherwife they would not be fufficient in an adult 
perfon to clofe up a wound which he had received when a 
boy; and a great quantity of the earthy part of our bo¬ 
dies goes off by urine, as is leen in fome difeafes. 
The caufe of the deftructton of the foil'd parts is in 
their perpetual extenfiou and retraction, at every pulfe of 
the heart, of which there are an hundred thoufand every 
day ; and by this motion even metals themfelves are worn. 
Other caufes are from the fried ion of the fluid againft the 
folid parts; from the wearing away of all the membranes 
which cover moveable parts, either on the furface or in 
the internal cavities of the body; in the alternate fwell- 
ing and fubfiding of the mufcles; and in the attraction and 
preffure which our fleflty parts exert. But all the parts 
of our body are the fo'oner worn away, in proportion as 
they are compofcd of a greater quantity of gluten and a 
ids quantity of earth; for that gluten when it is extend¬ 
ed, if the exteniion has been a little fu peri or to the force 
of its. cohefion, mud of neceility fall away and be carried 
off from the earthy parts. Thus wrinkles or furrows are 
generated; fuch as are vifible in the arteries of old men. 
The cellular texture, which otherwife would be diifojved 
Into water or jelly, is worn away by the impetus of the 
blood prefling againft the neighbouring blooa-veffels and 
mufcles, by friition, and by perpetual alternate flexion 
and extenfion. 
The decreafe would be very quick, and indeed there 
would be no great diftance between the beginning of our 
life and its end, uniefs thefe Ioffes were repaired. The 
fluids are quickly reftored by food, as appears from the 
example of a chicken, in which blood is generated out of 
its aliment within two days. The fat, however, and red 
globules of blood, are formed out of the fat; the lym¬ 
phatic juice from jelly ; the mucus from mucus ; and the 
reft of the humours from thefe and water. A gelatinous 
juice is brought from the aliments, through the arteries, 
to all parts of the body, and exudes into all parts of the 
cellular texture. The furrows, which we might imagine 
to be made in the inmoft arterial membrane by the impe¬ 
tus of the blood, are filled up by a vifeid matter brought 
into them by the lateral preffure; nor is it polllble that 
thefe furrows can be overfilled, becaufe every exuberant 
particle of nutritious juice muft necefl'arily be carried off 
by the-current of the blood. This juice will not be defi¬ 
cient while there is a fufficient quantity of aliment; and 
while there is more reft, and lefs reiiftance, in the bottom 
of the furrow than clfewhcre, which muft always be the 
cafe, becaufe the bottom is that part of the veffd which is 
at the greateft diftance from the main current of the blood 
flowing through it. There feem to be certain powers in 
the air, by which the aliment is attached to the folid parts, 
although we are ignorant of the' manner in which they a£t, 
The decreafe of the cellular texture arilirtg from at¬ 
traction or preffure, will be repaired by the vifeid vapour 
exhaling from the artery, and preffing towards thofe pla¬ 
ces which (land in need of reparation by the force of the 
neighbouring arteries and comprelTing mufcles, its aque¬ 
ous part being prefted out and reforbed. The gluten re¬ 
pairs mofl of the organic parts, tendons, and membranes; 
being formed into a new cellular texture, as in the foetus. 
The wafte which takes place in moveable parts adhering 
by their other extremity to the reft of the body, can be re¬ 
paired by protrufion alone, while the lymph fills up the in¬ 
tervals or hollows that are thus produced. 
When the growth of the body can proceed no farther, 
pbefity is produced, which is a kind of imitation of real 
growth. This proceeds from the fat generated by the ali¬ 
ment ; which by reafon of the impetus of the blood being 
leflfened, and its entering the fmalleft veffels with more 
difficulty, is carried to tire Tides of the veffels-; enters tire 
lateral ones and the inorganic pores of the arteries 5 exudes 
r o m y, 
into the cellular texture 5 and there, the power of con« 
qualfation of the blood, and the abforption by the veins, 
being now diminiftied, the fat is confequently colledeu. 
We feel the beginnings of decay even in youth itfelf. 
Even in that blooming feafon, the folid elements of the 
body are augmented, the chinks through which the hu¬ 
mours flow are leffened, fmali veffels are obliterated, and 
the greater attraction of the cellular texture has added a 
denlity to the whole body. Throughout the whole body, 
that hardnefs occafioned by age is very confpicuous, in 
the bones now wholly brittle, in the Ikin, in the tendons, 
in the conglobate glands, in the arteries, and likewife in 
the weight of all tire parts, and of the brain itfelf. The 
parts moft exercifed by motion fooneft grow rigid, as is 
obfervable in thole limbs of -mechanics which are moft 
ufed in their feveral occupations. Moreover, the arteries 
alfo continue to become more denfe, more narrow, and 
even to bo quite filled up, as well by the internal preffure 
of the blood flowing through the large arterial tube, as 
by the attraction of the cellular texture of which the 
greater part of the artery con ft ft's. An infinite number of 
parts of the cellular texture ceafe to be rumti filed; for 
the fmalleft arteries, which hitherto brought them nou- 
rifhment, are now obliterated, and ceafe to convey more 
nouriftiment. The extending force being removed, the 
cellular fiocculi draw themfelves together, contract the 
little fpaces intercepted between them, degenerate into 
membranes, or fubftances of a hard texture, which inter¬ 
cept, and as it were choke up, other veffels. , The gelati¬ 
nous vapour likewife concretes in the fmali hollows of the 
cellular texture, and unites with the (idps of thefe hol¬ 
lows into a hard folid. The mufcles degenerate into hard 
denfe tendons deftitute of all irritable power, becaufe the 
blood which they contained is expelled, and their fibres 
are condenfed, 
At the fame time the nerves become more and more cal¬ 
lous to the imprefftons of the fenfes, and the mufcles grow 
lefs fenfible to the folicitations of the animal powers; thus, 
the contractile force of the heart, the frequency of its 
j->u!fations, and confequently the whole force which drives 
the blood into the fmalleft veffels, are diminiftied. The 
quantity of humours is diminiftied in a denfe body, as is 
evident in the perfpiration, lemen, humours of the eye, 
and of the conglobate glands; the vapour alfo which be. 
dews the folid parts of the body every where dacreafes. 
For this reafon, nutrition now languifnes, becaufe there 
are more parts of the body which require nouriftiment, 
and lefs nutritious juice. Nor is the quantity of humours 
only diminiftied; they themfelves are likewife corrupted. 
They were mild and vifeid in children: but thefe fame 
humours are in oid men acrid, fait, foetid, with a great 
quantity of earth. This circumftance is owing to the ufe 
of fait or putrid food, which generate acrimony in the flu¬ 
ids; and the acrimony by a continual ufe of vitiated ali¬ 
ments perpetually increafes, being at the fame time aug¬ 
mented by a decreafed perfpiration and alvine evacuation 
neceffary for carrying off the putrid liquamen. Hence 
the fetor of the urine, of the breath, and the difficult 
healing of wounds. But the worft quality of the humours 
is, that they abound with earthy particles, which are ei¬ 
ther fuch as are collected infenliblV; from the aliments af¬ 
ter the fecretions have become lefs free, or fuch as are 
carried off from the folid parts and returned into the blood; 
as is proved by the prefence of earth in fome dileafes, 
and by the nature of the gouty earth, The quantity of 
this earth is continually increafmg, efpecially if the nu¬ 
tritious liquor abounds with it : hence the brittlenefs of 
the bones, and the hardnefs of all the other parts, increa¬ 
fes. This earth is likewife every where depofited in the 
cellular texture, but chiefly in the coats of the arteries, 
and produces crufts, which are at firft callous, and then of 
a bony or ftony nature. 
The hardnefs or rigidity of the whole body, the de¬ 
creafe of the raufcular powers, and the debility of the 
fenfes, conftitute old age,—an evil, alas 1 which fooner or 
law? 
