M . 
of acquiring the ufe of an inftrument fo important towards 
attaining the gratification of its daily increafing defires, and 
eftabliflung its communications with furrounding beings. 
The power of fpeech, however, like the ufe of the fenfes, 
and of the moving organs, is not polfelfed perfectly at 
once ; it is the offspring of laborious and repeated efforts. 
The vowel a (broad) is the molt eafily pronounced, as it 
requires only the opening of the mouth, and forcing out 
the air; the confonants, b,p, and m, require the lealt mo¬ 
tion of the organs, and are molt eafily articulated. The 
other founds are formed in proportion as the organs learn 
their offices. Some can articulate diltinctly, and repeat 
whatever is faid to them, at two years of age; but a longer 
time is generally neceflary. 
While the infant is thus flowly advancing in the deve¬ 
lopment of its powers, it is expofed to numerous and de- 
Itru&ive difeafes, which render its life very precarious for 
the three fir It years. In the fecond or third following 
years it becomes more certain ; and at fix or feven years of 
age a child has a better chance of living than at any other 
period of life. From the bills of mortality publilhed at 
London, it appears, that of a certain number of children 
born at the fame time, one-half of them die the three firft 
years; according to which, one-half of the human race 
would be cut off before they are three years of age. But 
the mortality among children is not every-where fo great as 
in London. M. Dupre de Saint-Maur, from a great num¬ 
ber of obfervations made in France, has fliown that half 
of the children born at the fame time are not extincl till 
feven or eight years have elapfed. Among the caules 
which have occafioned fo great a mortality among children, 
and even among adults, the fmall pox has been ranked as 
the chief. But luckily the means of alleviating the effects 
of this terrible fcourgeare now univerfally known by ino¬ 
culation. 
The period of infancy is followed by that of adolefcence. 
This begins, together with puberty, at the age of 12 or 14, 
and commonly ends in girls at 15, and in boys at 18, but 
fometimes not till 21, 23, and 25, years of age. According 
to its etymology (being derived from the Latin adolefcentia ), 
it is completed when the body has attained its full height. 
Thus, puberty becomes adolefcence, and precedes youth. 
This is the fpring of life; this is the feafon of pleafures, 
of loves, and of graces; but this fmiling feafon is of liiort 
duration. Hitherto nature feems to have had nothing in 
view but the prefervation and iticreafe of her work; (he 
Iras made no provilion for the infant except what is necef¬ 
lary for life and growth. It has enjoyed a kind of vegeta¬ 
ble exiffence which was (hut up within itfelf, and which 
it was incapable of communicating. In this firft ftage of 
life, reafon is (till afleep; but the principles of life i'oon 
multiply, and man has not only what is neceffary to his 
own exiffence, but what enables him to give exiffence to 
others. This redundancy of life can no longer be con¬ 
fined, but endeavours to expand and diffufe itfelf. 
Thus far we have followed Buffon in his animated (ketch 
of the progrefsof human life ; but here we muff leave him 
for a while, as we confider the pifture he has given of the 
approach of puberty and its correlponding circumffances 
to be lefs calculated io ferve the purpofes of fcientific in¬ 
formation, than to gratify idle and vicious curiofity, and 
roufe thofe pafftons which feldom require much excite¬ 
ment. The fubjefts of the procreation of the human fpe- 
cies, of pregnancy and parturition, are rtrihtly medical, and 
are treated of in fufficient detail under their proper heads 
i.i this work. 
Soon after the age of puberty, the body of man attains 
its full ftature. Some young people ceaie to grow after 
15 or 165 while others continue to increafe in height 
till 20, or even 23. During this interval they are ufually 
very (lender, but by degrees the limbs fwell, and aflume 
their proper (hape; and before the age of 30, the body 
has generally attained its greateff perfection with regard 
to ltrength, confidence, and fymmetry. Adolefcence is 
confidered as terminating at the age of zo or 25, and at 
r\ N. 251 
this period (according to the ufual divifion of man’s life 
into ages) youth begins. This continues till the age 
of 30 or 35. 
The Itature of a man varies confiderably in different 
climates, and under different circumffances. Authors are 
by no means agreed as to what (houid be confidered the 
medium height of the human body. Buffon dates it at 
from five feet and an inch, to five feet four inches, making 
the medium height about five feet two inches. Haller on 
the contrary, reckons the true medium height of men in 
the temperate climates of Europe, to be about five feet 
five or fix inches. In general, women are a few inches 
(horter than men. It has been remarked by Haller, that 
in mountainous countries, fuch as Swifferland, the inha¬ 
bitants of the plains are commonly much taller than thofe 
of the higher fituations. It is difficult to afcertain with 
precifion the actual limits of the human Itature; but we 
may remark that, in furveying the inhabited parts of the. 
earth, we find more remarkable differences in the ftature 
of different individuals of the fame nation than in the 
general height of different nations. In the fame climate, 
among the lame people, and often even in the fame family, 
we find forne individuals that are far above the medium 
ftandard, and others as far below it. The former we call 
Giants, and the latter Dwarfs. See thofe articles. 
The body, having acquired its full height during the 
period of adolefcence, and its full dimenhons in youth,, 
remains for fome years in the fame (late before it begins 
to decay. This is the period of manhood, which extends 
from the age of 30 or 35 to that of 40 or 45 years. Du¬ 
ring this ltage, the powers of the body continue in full 
vigour; and the principal change which takes place in the 
human figure a rile a from the formation of fat in different 
parts. 
Phyfiologifts give the name of old age to that period of 
life which commences immediately after the age of man¬ 
hood, and ends at death 5 and they diftinguilh green old 
age from the age of decrepitude. But in our opinion fuch 
an exteniive fignification of the word ought not to be ad¬ 
mitted. We are not old men at the age of 40 or 45 ; and, 
though the body then gives figns of decay, it has not yet 
arrived at the period of old age. Daubenton obferves, 
that it would be more proper to call it the declining age , 
becaufe nature then becomes retrograde; the fatnels and 
good plight of the body diminifh, and certain parts of it 
do not perform their functions with equal vigour. See 
the article Liff,, vol. xii. p. 639, 40. 
Man has no right to complain of the (liortnefs of life. 
Throughout the whole of living beings, there are few 
who unite in a greater degree all the internal caules which 
tend to prolong its different periods. The term of geffa- 
tion is very confiderable; the rudiments of the teeth are 
very late in unfolding; his growth is (low, and is not 
completed before about twenty years have elapfed. The 
age of puberty, alfo, is much later in man than ih any 
other animal. In (hort, the parts of his body, being coivi- 
pofed of a fofter and more ffexiole lubftance, are not 10■ 
ioon hardened as thofe of inferior animals. Man, there¬ 
fore, feems to receive at his birth the feeds of a long life; 
if he reaches not the diftant period which nature leemed 
to proinife him, it muff be owing to accidental caufss fo¬ 
reign to himfelf. Inftead of faying that lie has finilhed his 
life, we ought rather to fay that he has not completed it. 
The natural and total duration of life is in lome mea- 
fure proportioned to the period of growth. A tree or an 
animal which loon acquires its full fize, decays much 
fooner than another which continues to grow for a longer 
time. If it is true that the life of animals is eight times 
longer than the period of their growth, we might conclude 
that the boundaries of human life may be extended to a 
century and a half. 
On the lubjefl of longevity , and the general circum- 
(tances on which it depends, we have already treated un¬ 
der the article Life, vol. xii. p. 634. and Have there given 
a lift of a great number of perfons who have been cele- 
5 b»ated i 
