586 ERA OF MIND. 



which the three grand continental divisions of Europe, Asia, and 

 Africa radiate. 



No creations since that of Man. — It is not known that any new spe- 

 cies of plants or animals have appeared on the Earth since the 

 creation of Man. 



III. Changes of level on the Earth's surface. 



Although the earth, in this its last age, has reached a state of 

 comparative stability, changes of level in the land still take place. 

 The movements are of two kinds : — 



1. Secular, or movements progressing slowly by the century. 



2. Paroxysmal, — taking place suddenly, in connection usually 

 with earthquakes. 



1. /Secular. — The secular movements which have been observed 

 are confined to the middle and higher temperate latitudes, and are 

 evidently a continuation of the series which characterized the Post- 

 tertiary period. In this and other dynamical changes the Post-ter- 

 tiary and the age of Man have intimate relations. The movements 

 of the former were directly anticipatory of the latter. 



The coast of Sweden and Finland on the Baltic has been proved, 

 by marks made under the direction of the Swedish government, 

 to be slowly rising. The change is slight at Stockholm, but in- 

 creases northward, and is felt even at the North Cape, — an extent 

 north and south of one thousand miles. Lyell, in 1834, estimated 

 the rise at Uddevalla at nearly or quite four feet in a century, and 

 he made it still greater to the north. The fact of the slow elevation 

 was first suspected a century and a half since. Here, then, is slow 

 movement by the century, such as characterized the great changes 

 of level in past ages. 



Beds of recent shells are found along the coast at many places, at 

 heights from 100 to 700 feet. Part of these may be of Post-tertiary 

 date. Two miles north of Uddevalla, Lyell found barnacles on the 

 rocks over 100 feet above the sea ; and there are shell-beds at a 

 height of 400 feet. The former at least belong probably to the pre- 

 sent era. Southwest of Stockholm other beds of shells occur, and 

 the same dwarfish species that now live in the partly-freshened 

 waters of the Bothnian Gulf. 



There are also near Stockholm proofs of a former subsidence 

 since fishing-huts were built on the coast. A fishing-hut, having a 

 rude fireplace within, was struck, in digging a canal, at a depth of 

 sixty feet. It is a common belief that over southern Sweden a 

 very slow subsidence is now in progress. 



