38 ON THE TERM " TRANSITION." p&i. VIII. 



At length, after much controversy, the doctrine of the igneous origin of 

 trap and granite made its way into general favor ; but although it was, in 

 consequence, admitted that both granite and trap had been produced at 

 many successive periods, the term primitive or primary still continued to 

 be applied to the crystalline formations in general, whether stratified, like 

 gneiss, or unstratified, like granite. The pupil was told that granite was 

 a primary rock, but that some granites were newer than certain secondary 

 formations ; and in conformity with the spirit of the ancient language, to 

 which the teacher was still determined to adhere, a desire was naturally 

 engendered of extenuating the importance of those more modern granites, 

 the true dates of which new observations were continually bringing to light. 



A no less decided inclination was shown to persist in the use of the 

 term " transition," after it had been proved to be almost as faulty in its 

 original application as that of flotz. The name of transition, as already 

 stated, was first given by Werner, to designate a mineral character, inter 

 mediate between the highly crystalline or metamorphic state and that of 

 an ordinary fossiliferous rock. But the term acquired also from the first 

 a chronological import, because it had been appropriated to sedimentary 

 formations, which, in the Hartz and other parts of Germany, were more 

 ancient than the oldest of the secondary series, and were characterized by 

 peculiar fossil zoophytes and shells. When, therefore, geologists found 

 in other districts stratified rocks occupying the same position, and inclosing 

 .similar fossils, they gave to them also the name of transition, according 

 to rules which will be explained in the next chapter ; yet, in many cases, 

 such .rocks were found not to exhibit the same mineral texture which 

 Werner had called transition. On the contrary, many of them were not 

 more crystalline than different members of the secondary class ; while, 

 on the other hand, these last were sometimes found to assume a semi- 

 crystalline and almost metamorphic aspect, and thus, on lithological 

 grounds, to deserve equally the name of transition. So remarkably was 

 this the case in the Swiss Alps, that certain rocks, which had for years 

 been regarded by some of the most skilful disciples of Werner to be tran- 

 sition, were at last acknowledged, when their relative position and fossils 

 were better understood, to belong to the newest of the secondary groups ; 

 nay, some of them have actually been discovered to be members of the 

 lower tertiary series ! If, under such circumstances, the name of transition 

 was retained, it is clear that it ought to have been applied without refer- 

 ence to the age of strata, and simply as expressive of a mineral peculiarity. 

 The continued appropriation of the term to formations of a given date, in- 

 duced geologists to go on believing that the ancient strata so designated 

 bore a less resemblance to the secondary than is really the case, and to 

 imagine that these last never pass, as they frequently do, into metamor- 

 phic rocks. 



The poet Waller, when lamenting over the antiquated style of Chaucer, 

 complains that — 



"We write in sand, our language grows. 

 And. like the tide, our work o'erflows. 



