Prof. Necker on the History and Progress of Geology. 
period, by similar means, and under similar circumstances. In 
other words, he subdivided the great classes of primitive and se- 
condary rocks, into particular and independent groups, which 
he classed according to their relations of superposition and anti- 
quity. 
The establishment of Formations is the most fertile idea which 
has sprung from the intellect of this illustrious man ; it enlarges 
the point of view, and, at the same time, simplifies the field of 
observation. It was also a happy distinction which he made, 
when he separated from both the Primitive and Secondary, that 
class of rocks which is intercalated between them, and which 
equally participates of the nature of both. This innovation, the 
propriety of which has been often disputed, has, nevertheless, 
been retained even by those very persons who have attacked it ; 
and the division of Transition-rocks has been respected, because 
founded upon the basis of nature. 
In short, Werner may be regarded as the creator of that por- 
tion of the science which he has named Geognosy, and which 
treats especially of the superposition of mineral masses. To so 
many claims to the gratitude of geologists, Werner has still add- 
ed that of having formed, by his example, a multitude of dis- 
tinguished naturalists, who, having acquired at Freyberg a pas- 
sion for the study of minerals, have carried with them into the 
different countries of Europe, the principles of observation and 
the doctrine of their master. Jameson and Weaver in Great 
Britain, D’Aubuisson and Brochant in France, Brocchi in Italy, 
Charpentier in Switzerland, and Humboldt and Von Buch in 
Prussia, have excited a high idea of the school in which they 
have studied. 
Observations, however, had multiplied; and their relations to the 
types of Werner seemed to become always less and less distinct ; 
insomuch, that geologists no longer understood each other *. The 
labour of reconciling these different opinions was undertaken by 
the celebrated Humboldt, who, originally a pupil of Werner, 
had extended his observations not only over the two Americas, 
but also over the greater part of Europe. His work is an inesti- 
mable treasure of accurately observed facts ; it is the most me- 
* This misunderstanding existed only with those ignorant of the facts and 
principles of the Wernerian Geognosy.— Edit. 
