436 Report of the Progress of the Sciences in France. 
d. by the currents which take place at sea; e. by those whicfi 
take place in lakes ; f. by the currents of rivers; g. by catastro- 
phes which have happened on the surface of the globe, 
CATASTROPHES ON THE SURFACE OF THE GLOBE. 
Geologists, proceeding upon the various facts exhibited by 
the theory of the earth, conclude, with the priests of Memphis 
and all subsequent philosophers, that various catastrophes, 
more or less considerable, have happened on the earth’s sur- 
face. Some even suppose that there have been general cata- 
strophes, , 
‘In my Theory of the Earth I have cited the following causes 
as likely to have produced these particular catastrophes : viz. 
1. Particular Inundations.—a. Abundant rains which have 
swoln the streams of the Nile, the Niger, and the Menau. 
b. Overflowings of lakes, of which history makes mention. in 
abundance : such were the deluges of Ogyges, Deucalion, Pro- 
metheus, &c. c. Violent winds have produced great inundations 
in Holland, by swelling the sea, as in 1218 and 1646. 
These sea waters have remained a more or less considerable. 
time on peat mosses and other strata formed in fresh water, and 
deposited fossil shells. Poiret observed near Soissons peat 
mosses containing fluvial shells, covered with strata containing 
sea shells, cerites, venuses, and oysters, 
d. Explosions of snbterraneous fires throw up part of the sea, 
aud cause particular inundations. . 
e. The fall of some mountains has produced some local in- 
undations. 
2. Earthquakes have occasioned many singular catastrophes 
on the surface of the globe; but these have been confined to 
certain countries only. That of Lisbon in 1755 shook some 
countries very distant ; but its effects were far frem producing 3 
general catastrophe. 
The dreadful explosions of the enormous volcanoes of Mexico 
and Peru produce only limited catastrophes. 
3. The passage of a comet close to the earth has also been 
regarded as a cause which must have produced a great cata- 
strophe on the surface of the globe, by swelling the waters of 
the ocean ; but all astronomers are now agreed that this hypo- 
thesis has no probable foundation. 
4. But there is another cause which ought to produce, after 
some centuries, great changes on our globe: this is the increase 
of its mass, which I] have proved ought to take place. I have 
said, in my Theory of the Earth, that “a great part of the 
secondary strata is formed of the remains of organized beings : 
such are the bitumens which form immense and very deep ay 
(OSSi 
