INTRODUCTION. 79 



with other forms of matter effects important changes. Upon 

 this physical basis, Breislak supposes that, as the heat-particles 

 entered into combination with other particles of matter for 

 which they had affinity, the total amount of free heat 

 diminished, and the temperature of the earth perceptibly 

 cooled. Gaseous material gathered internally and still more 

 at the surface, where it was condensed as a primitive ocean. 

 The internal gases in combination with heat produced elastic 

 vapours. These tried to force their way to the surface, 

 cracking and breaking the solid crust that had begun to 

 form. 



Breislak then discusses the origin of the various kinds of 

 crystalline rock found in the crust. He disagrees with 

 Hutton's explanation of gneiss and crystalline schist as 

 altered sedimentary rock, and includes them together with 

 granite, porphyry, and other igneous rocks, as products of the 

 cooling of matter from the primitive molten state. Breislak's 

 ideas about rock-structure soon fell into oblivion, but his able 

 criticism of the Neptunian dogmas was largely instrumental in 

 eradicating them from the teaching of the universities and 

 colleges. There would be little profit in recording further 

 the many contradictory theories of the earth that appeared 

 between the publication of Buffon's Theorie de la Terre in 

 1749 and of Breislak's Introduzione alia Geologia in 1811. 

 What seems very remarkable is that in none of these can we 

 trace the influence of the cosmogony and geogeny made known 

 in 1755 by the great philosopher, Immanuel Kant, in his 

 Naturgeschichte des Himmels. Neither do geologists seem 

 to have benefited by the kindred work of the French mathe- 

 matician, Laplace, Exposition du Systeme du Monde, published 

 in 1796. 



Kant's little book appeared anonymously, immediately before 

 the outbreak of the Seven Years' War. It received no atten- 

 tion, was forgotten, and ninety years elapsed before Alexander 

 von Humboldt unearthed it from neglect. Kant originated 

 the conception that the ordered cosmical universe might have 

 been produced merely by the agency of mechanical forces 

 acting upon a vaporous chaotic mass. Kant supposed that all 

 the matter composing the spherical bodies of our solar system, 

 the planets and the comets, was in the beginning broken up 

 into its elementary constituents and distributed throughout 

 space. All the particles of matter could attract and repel one 



