THE FORTIETH PARALLEL SURVEY. 609 



sediments. There cannot be a stratified deposit laid down upon a pre- 

 existing surface, conforming to its irregularities in such a manner as to 

 present itself in the form of continuous layers. Yet Mr. Emmons 

 describes such a phenomenon : hence the only conclusion following his 

 views is that the solid gi-anite slid up along the bottom of the quartzite, 

 bending it so as to cause it to conform with the irregularities of the gran- 

 ite, and this elevation of the solid gi-anite must have metamorphosed 

 the limestone, and corrugated and uptilted all the adjacent formations ; 

 yet with all this the gentlemen studying the locality fail to show any 

 evidence that the granite was solid at the time. Is it possible that an 

 enormous mass of rough jagged granite could have been pushed like a 

 huge rasp in contact witlj quartzites, limestones, etc., and have left no 

 trace of its movement upon them] So, too, if it were intrusive, it 

 should in like manner show by its contacts that such was the case. 

 Instead of raising so extraordinary a fiibric of theory on so slender a 

 basis of facts, it would have been better to study the region a little 

 more thoroughly. To us it appears highly probable that the granite 

 was of eruptive origin, and of later than Archaean age. It is certain 

 that the section of the Wahsatch Range given in the Atlas of the 

 Fortieth Parallel Survey does not conform to the theories of Messrs. 

 King and Emmons ; and, moreover, that it represents impossible strati- 

 graphical conditions. 



Views very similar to those here expressed by the writers of this 

 paper have already been published by Professor Geikie, Director of the 

 Geological Survey of Great Britain, in an article having as its title, " On 

 the Archtean Rocks of the Wahsatch Range " (Am. Jour. Sci., 1880, 

 (3) XIX., pp. 363-367). From this paper the following extract is made, 

 and it Avill be a sufficient indication of the light in which Mr. Geikie 

 regards the geological speculations of ]Messrs. King and Emmons touch- 

 ing the structure and age of the range in question. 



" According to the Reports of the Exploration of the 40th Parallel, the Wah- 

 satch Mountains consist of a central core of Archsean rocks, composed partly of 

 granites and partly of various quartzite, schists, and other crystalline masses. 

 These rocks are represented as having formed an island in the Paleozoic sea ; 

 and Mr. King asserts that the island must have presented to the west an 

 almost precipitous face of 30,000 feet, or upwards of Similes — an altitude 

 exceeding that of any mountain chain. Round this lofty Archjean island the 

 whole of the Paleozoic and Mesozoic sediments are said to have been deposited 

 to a depth of from 30,000 to 40,000 feet, in one continuous uninterrupted 

 series. Subsequent terrestrial movements, acting along the line of the original 

 island, have upraised the surrounding sedimentary masses, and the ancient 



