LAMARCK'S WORK IN GEOLOGY \\y 



by displacing and again bringing together the mole- 

 cules composing them, so that, undergoing a new- 

 aggregation, these calcareous molecules obtained a 

 number of points of contact, and constituted harder 

 and more compact masses. It finally results that 

 instead of the original masses of madrepores and 

 millepores there occurs only masses of a compact 

 calcareous rock, which modern mineralogists have 

 improperly called primitive limestone, because, seeing 

 in it no traces of shells or corals, they have mistaken 

 these stony masses for deposits of a matter primi- 

 tively existing in nature." 



He then reiterates the view that these deposits 

 of marble and limestones, often forming mountain 

 ranges, could not have been the result of a universal 

 catastrophe, and in a very modern way goes on to 

 specify what the limits of catastrophism are. The 

 only catastrophes which a naturalist can reasonably 

 admit as having taken place are partial or local ones, 

 those dependent on causes acting in isolated places, 

 such as the disturbances which are caused by vol- 

 canic eruptions, by earthquakes, by local inundations, 

 by violent storms, etc. These catastrophes are with 

 reason admissible, because we observe their analogues, 

 and because we know that they often happen. He 

 then gives examples of localities along the coast of 

 France, as at Manche, where there are ranges of high 

 hills made up of limestones containing Gryphaeae, 

 ammonites, and other deep-water shells. 



In the conclusion of the chapter, after stating that 

 the ocean has repeatedly covered the greater part of 

 the earth, he then claims that " the displacement 

 of the sea, producing a constantly variable inequality 



