1'jO E A R T H. 
Thall render that difquifition ufelefs to om' prefent pur- 
pofe. If the natural operations which, according to your 
opinion, are to deftroy our continents, go on fo (lowly 
1 hat there is no trace upon the furface of the earth, nor 
any record in the memory of man, by which we may 
judge when thofe operations began, their beginning mu ft be 
very remote ; and you think it (o. But 1 will (hew you, 
that we have both thefe forts of documents, by which it 
is demonftrated that our continents are not old ; which dc- 
monlhation will render it ufelefs, in refpedt of your the- 
ory, to determine how long thefe continents will lad. 
This brings me to a different kind of furvey of our 
continents, which I (hall introduce by your own expref- 
bons. “ We are inveftigating, you fay, p.297, the age 
of the prefent land, from the beginning of that body which 
was in the bottom of the fea .” Having thus announced the 
objedt of your inveftigation, we were to Qjcpedt a conclu- 
fion relating to time pajl ; but in the clofe of your in¬ 
quiry, we find its objedl entirely different; the conclu- 
fion relates to future timet “ It is in vain, you fay, p. 293, 
to meafure a quantity which efcapes our notice, and 
which hiftory cannot afeertain : we might juft as well 
attempt to meafure the diftance of the ftars without a 
parallax, as to calculate the dcfruElion of the folid land 
without a meafure correfponding to the whole.’' Permit me 
to reprefent to you, that with the view of inveftigating 
the age of the prefent land, an inquiry refpedling the time 
in which its dcfruElion (hall be completed, was far from 
your purpofe. It is not furprifing that you find no means 
of calculation in this refpedf, fince the operation that you 
fuppofe going on, does not exift ; our continents are cer¬ 
tainly not defraying : but you might have acquired, by 
various means, a diftindl idea of their age ; for we fee 
on them many forts of (ffeEls, which, from the nature of 
their caufes, inuft have had their origin at the beginning 
bf that body which , before, was in the bottom of the fea ; and 
diftindl parts of thofe ejfeEls, produced in known times, are 
comparable to the whole. This new inquiry will relate to 
fome of the fame diffindtive parts of the furface of our 
continents, as were the objedls of the former; continued 
changes tending to a maximum , are their charadleriftics. I 
isave already proved that tendency, as relating to future 
time-, and now I (hall examine the fame changes, in their 
correfpondence with time paf. 
In returning, for the prefent purpofe, to the tops of 
©ur mountains, I (hall begin a ftep higher than in the for¬ 
mer difquifition. I had then only to colledt, without 
any pofiibility of lofs, all the fragments feparated from 
thofe high grounds by natural caufes : therefore I pafted 
over the central ridges of their great chains ; it being 
fufficient to take notice of thofe fragments , by meeting 
them in certain . padages, where they muft firft gather, 
before they fall into the beds of the main ftreams ; the 
only conveyance for them out of the mountains : but we 
(hall have a number of interefting objedls to ftudy in 
thofe high regions, where the characters of decay l'eem 
fo ftrongly imprefted, that to thofe who arrive there un¬ 
informed, they muft appear as the tomb-ftones of our 
continents. However, from thofe towering monuments 
of devaftation, to tire deep hillock rifing over a fmooth 
plain, there is no difference, either in the general caufes 
of their definition, or in the inference that may be drawn 
from them, to determine the age of our continents: all 
thofe grounds came out of the fea in a much more rugged 
(late than that in which they now appear; which (late 
has been the original caufe of their decay, and whatever 
be .their height, if they are (fill abrupt, the operation 
which tends to fmooth them is not finiihed. 
It is unn'eceirary to enlarge on the proof, that all the 
fteep high grounds of our continents came out of the fea in 
tiie fame decaying (lute in which they now are. Abrupt 
Tides of mountains, fometimes many thoufand feet high, 
exhibit the JcElions of numberlefs frata, the molt part of 
which are c.onfiderably out of the horizontal pofition in 
which they muft have been formed. Confequently, thofe 
feElions, and a fortiori thofe of 1 efs magnitude, but having 
the fame charadlers, muft have been the effedt of fome 
caufe- which had the power of overturning the whole 
mat's of the frata themfelves. So far we cannot but 
agree ; for your theory on the formation of our continents 
is founded, as well as mine, on caufes which muft have 
produced fuch a diforder ; and in refpedt of the continents 
once dry, we agree alfo, that no other caufes of altera¬ 
tion can be admitted, than thofe which are (till in adtion. 
This then ought to be fufficient to eftablifti, thafi the 
great chafms of our continents exifted at their origin ; but 
as many other queftions depend on that primary one, I 
muft treat it more particularly. 
The huge ruins of high mountains inclofe, in the molt 
chaotic manner, immenfe fpaces, now vacant, though 
they muft have been filled, formerly, with the continua¬ 
tion of the fame frata, the remains of which now fur- 
round them. This is a very ftrong feature of our conti¬ 
nents, which muft ftrike every beholder capable of feeling 
aftoniftiment at the wonders of nature ; and he will a(k 
himfelf, “ What is become of the immenfe bulk of ma¬ 
terials which are miffing in thofe vacancies ?” This then 
is the firft and precife object which muft excite the at¬ 
tention of the curious, with refpedt to geologic fy(terns ; 
but at the fame time it muft create a juft diffidence of 
every fyftem which does not give a clear and fatisfadtory 
account of fuch finking monuments of revolution. It is 
not even neceffary to travel in mountains, in order to re¬ 
ceive the impreffion of thofe wonderful objedts: landfcape 
painters and et»gravers have fpread their pidtures in every 
clafs of dwellings, from the fumptuous palace to the hum¬ 
ble cottage ; fteep mountains, threatening rocks, deep¬ 
winding valleys, waterfalls, tumultuous torrents, foam- 
ng between tumbled mafies of impending caves, are the 
objedls which they commonly intermix with fofter feenes, 
for pidlurefque effedt; and far from ever exceeding na¬ 
ture in that ruinous appearance of fome parts of our land, 
they muft ever remain much below the ftupendous feenes 
which they attempt to reprefent. 
If it were not for the vague idea of fome geologifts, 
that the running waters, working, ages* after ages, on the 
furface of our continents, have ploughed down their deep- 
eft valleys, and have formed the hills, either by fcooping 
the foil round them, or by raifing heaps of rubbifh, every 
attentive man would confider thofe objedls with a. cu¬ 
rious eye ; and finding on every feep ground evident marks 
of a continued decay, it would naturally occur to his mind, 
that fuch an operation muft have had a beginning, not im- 
poffible to be determined ; and that its difeovery might 
lead to fome great event in the hiftory of our globe. I 
(hall then firft remove that caufe of incuriofity, by prov¬ 
ing, that the land-waters, thofe which have run over the 
furface of our continents ever fince they exifted, have had 
no (hare whatever in the produdlion of the ruinous ap¬ 
pearance of fo many of their parts, except along the im¬ 
mediate channel of fome ftreams : for if that queftion is 
once determined beyond the power of difpute, the phe¬ 
nomena which I have deferibed, will re-aflume the power 
that they ought to have had long fince on thofe who 
think nature worth obferving : and that attention will 
anfwer a greater purpofe than is commonly thought ; 
which I will explain when all the previous queftions 
have been thoroughly examined. 
The icy valleys of the Alps are now known to moft cu¬ 
rious travellers ; it is become the fafliion to vifit them : 
let then fajhion be, in this inftance, ufeful to mankind, 
by afeertaining fome fadts, the light of which, being 
fpread over all the phenomena of the fame kind, will 
render them equally great in their confequences. To the 
vilitors of the Alps then, I appeal, for the exactnefs of 
what I am going to deferibe ; and from fome of them I 
expedt, that by their example, they will excite curiofity 
and attention to numberlefs objecls, not fo ftupendous, 
but equally important in the hiftory of the earth. Lofty 
and abrupt ranges of pyramidal rocks are the wonderful 
4 borders 
