LON 
LON 
LON 
83 
•chalky, or sandy soils. It is advantageously 
cultivated along with clover, and springs ear- 
lier than other grasses, supplying food for 
cattle at a time when it is most difficult to be 
obtained.- Cows, horses, and sheep, eat it ; 
goats are not fond of it. 
2. Thetenuilentum, or white darnel, grows 
spontaneously in ploughed fields. If the 
seeds of this species are malted with barley, 
the ale soon occasions drunkenness ; mixed 
with bread-corn, they produce but little ef- 
fect, unless the bread is eaten hot. 
LONCIHTTS, spleenzvort, a genus of the 
cryptogamia filices class of plants, the fructi- 
fications of which are arranged into lunulated 
series, and disposed separately under the si- 
nuses of the leaves. There are five species. 
The leaves of this plant are of use in healing 
wounds, and in preventing inflammations of 
them: they are also used against the spleen. 
The root is aperient and diuretic. 
LONGEVITY, long life. The duration 
of human life is a subject so universally in- 
teresting, that instances of persons who have 
considerably exceeded the usual term of life 
have at all times attracted notice, although 
very few attempts have been made to ascer- 
tain the circumstances under which life may 
be prolonged to its greatest extent. Buffon, 
Haller, Dr. Folhergill, Dr. Barton, Dr. 
Hufeland, and a few others who have noticed 
this subject, appear to have considered but 
a very small number of the instances of lon- 
gevity which have occurred. Mr. J. Easton, 
in order to supply better materials for others, 
published, a few years since, a much greater 
collection of instances of this kind, though 
probably but a small part of what have actu- 
ally occurred. His list consists of 1712 per- 
sons, who are stated to have died at the fol- 
lowing ages: 
Ages. Persons. 
From 100 to 110 years 
1310 
1 10 to 120 
277 
120 to 130 
84 
130 to J 40 
26 
140 .to 150 
7 
150 to 160 
3 
160 to 170 
2 
170 to 185 
3 
1712 
Such a number of instances 
would 
many useful conclusions ; but most accounts 
of this kind contain little more than the name, 
age, and place of the death of the person 
mentioned, from which of course little infor- 
mation can he gained. Sir J. Sinclair, in an 
Essay on Longevity, has endeavoured to ex- 
cite a more general interest on this subject, 
which lias by no means been investigated with 
the attention it deserves. 
That longevity depends principally on con- 
formity of conduct to the laws of nature, ap- 
pears an indisputable fact; but from all the 
observations which have been made, it like- 
wise appears, that there are other circum- 
stances which have considerable influence : 
of these perhaps the most certain is descent 
from long-lived ancestors. Dr Rush, of Phi- 
ladelphia, remarks, that lie has not found a 
single instance of a person who had lived to 
be "so years old, of whom this was not the 
case; and the accounts collected by others 
strongly confirm this observation. 
The climate of some countries has been 
supposed to be much more favourable to 
longevity than others : thus Mr. White- 
hurst asserted, that Englishmen in general 
were longer-lived than North, Americans; 
and Mr. W. Barton has since endeavoured 
to prove the contrary: but whatever infer- 
ences of this kind national partiality may 
attempt to support, more extensive observa- 
tions will in general confirm the conclusion, 
that although longevity evidently prevails 
more in certain districts than in others, and 
those regions which lie within the temperate 
zones are best adapted to promote long life, 
yet it is by no means confined to any parti- 
cular nation or climate, as remarkable in- 
stances of it may be produced both from 
very hot and very cold countries. It is 
highly probable that the human frame is so 
constituted as to adapt itself easily to the at- 
mosphere* and peculiarities of the country in 
which it receives life, or even into which it 
is afterwards removed. Thus France and 
Sweden are countries differing materially in 
soil and climate: the general mode of life of 
the inhabitants is likewise very different; 
yet the usual rate of mortality has been found 
nearly the same in both. Men can live 
equally well under very different circum- 
stances. It is sudden changes that are inju- 
rious ; and temperate climates being less 
liable-'-to such changes, are found to be most 
favourable to the continuance of life. There 
are, however, in almost every country, par- 
ticular districts more favourable to the health 
of the inhabitants than others; and the cause 
of this superiority is chiefly a free circulation 
of air, uncontaminated with the noxious va- 
pours and exhalations which destroy its pu- 
rity in other parts ; thus hilly districts are 
almost universally found more healthy than 
low and marshy places, or than close and 
crowded cities. 
From a list of 14.7 persons who are .record- 
ed to have lived to the age of 120, years and 
upwards, it appears, that more than half 
were inhabitants of Great Britain, viz. 
63 of England and Wales, 
23 of Scotland, 
29 of Ireland, 
30 of other countries. 
The number of instances in Scotland, com- 
pared with those of England, appears by this 
account to have been more than twice the 
proportion of the population, which certainly 
seems to shew that the climate of the former 
is very favourable to long life. The great 
proportion of inhabitants of Great Britain and 
Ireland, though perhaps arising in some mea- 
sure from instances of great age not being 
so generally noticed and recorded in other 
places, at least shews, that these countries 
are not unfavourable to longevity. 
It is a fact pretty well established, that 
more males are born than females; it is also 
well known, that in almost every form which 
animal life assumes, the male appears to pos- 
sess a somewhat superior degree of bodily 
strength to the female,. From these circum- 
stances it might be expected that the num- 
ber of males living would be found greater 
than that of the females, and that in general 
they would enjoy a greater duration of life ; 
the contrary, however, lias been asserted, 
and evidence produced which appeared to 
justify such an opinion ; but it seems pro- 
bable, that in forming the accounts from 
which the number of females living appeared 
greater than that of the males, sufficient at- 
tention was not paid to the number of males 
engaged chiefly abroad in the army and 
navy, and of the emigrations to foreign parts 
being chiefly of males. That the male con- 
stitution is naturally more durable than that 
of females, may be inferred from the list 
before referred to of 145 persons, who have 
attained unusually great age, more than two- 
thirds of the number being males. Dr. 
Hufeland remarks, that the equilibrium and 
pliability of the female body seems, for a cer- 
tain time, to give it more durability, and to 
render it less susceptible of injury from de- 
structive influences than that of men ; but 
that male strength is, without doubt, neces- 
sary to arrive at a very great age. More 
women, therefore, become old, but fewer 
very old ; and if the registers of mortality, 
from which tables of the probability of the 
duration of human life are formed, were more 
extensive, and comprehended a greater num- 
ber of years, so as to include the instances 
of great longevity, the difference between 
the value of male and female lives would 
appear less than it is supposed to be, and 
probably the sum of life of the whole of 
each sex approaches very nearly to equality. 
The form of the individual appears to be 
of considerable importance: moderate-sized 
and well-proportioned persons have certainly 
the best chance of long life. There are, how- 
ever, a few instances of persons of a different 
description having attained considerable age. 
Mary Jones, who died in 1783, at Wern, in 
Shropshire, aged 100 years, was only two 
feet eight inches in height, very deformed and 
lame; and James M ‘Donald, who died near 
Cork in the year 1760, aged 117, was seven 
feet six inches high. 
Matrimony, if not entered into too early, 
appears to be very conducive tojiealth and 
longlife, the proportion of unmarried persons 
attaining great age, being remarkably small ; 
Dr. Rush says, that in the course of his en- 
quiries, he met with only one person beyond 
eighty years of age, who had never been mar- 
ried.’ This is a very limited remark; Mrs. 
Mahon, who died in 1733, aged 105 ; Ann 
Kerney, who died the same year, aged 110; 
Martha Dunridge, who died in 1752, in the 
100th year of her age ; and Mrs. Warren, 
who died in 1753, aged 104, had never been 
married : and in the list prefixed to sir John 
Sinclair’s Essay on Longevity, of pensioner? 
in Greenwich hospital, who were upwards of 
eighty years of age, there are sixteen who 
never were married : the same list, however, 
contains five times as many persons who had 
been married, and other accounts are in a 
still greater proportion. 
The Chinese erect triumphal or honorary 
arches to the memory of persons who have 
lived a century, thinking, that without a so- 
ber and virtuous life it is impossible to attain 
so great an age. Temperance is certainly 
the best security of health; and no man can 
reasonably expect to live long who impairs 
the vital powers by excess, which converts 
the most natural and beneficial enjoyments 
into the most certain means of destruction. 
The few instances of individuals who, not- 
withstanding their licentious mode of life, 
have attained considerable age, cannot be 
put in comparison with the immense number 
whose lives have been materially shortened 
