LITERARY NOTICES. 



127 



tinent, has shown that the series of actions 

 which we have described as occurring in the 

 Alps took place in the same order in the for- 

 mation of all mountain -masses. It is doubt- 

 ful whether the line of weakness is always 

 betrayed in the first instance by the formation 

 along its course of volcanic fissures. But in 

 all cases we have evidence of the production 

 of a geosynclinal, which is afterward, by lat- 

 eral pressure, converted into a geanticlinal, 

 and from this the mountain-chains have been 

 carved by denudation. Professor Dana has 

 shown that the geosynclinal of the Appala- 

 chian chain was made up of sediments attain- 

 ing a thickness of forty thousand feet, or eight 

 miles; while Mr. Clarence King has shown that 

 a part of the geosynclinal of the Rocky Moun- 

 tains was built up of no less than sixty thou- 

 sand feet, or twelve miles of strata. 



It has thus been established that a very 

 remarkable relation exists between the forces 

 by which continental masses of land are raised 

 and depressed and mountain-ranges have 

 been developed along lines of weakness sep- 

 arating such moving continental masses and 

 those more sudden and striking manifestations 

 of energy which give rise to volcanic phe- 

 nomena. It is in this relation between the 

 widespread subterranean energies and the 

 local development of the same forces at vol- 

 canic vents that we must in all probability 

 seek for the explanation of those interesting 

 peculiarities of the distribution of volcanoes 

 upon the face of the globe which we have de- 

 scribed in a former chapter. The parallelism 

 of volcanic bands to great mountain-chains is 

 thus easily accounted for ; and in the same 

 way we may probably explain the position of 

 most volcanoes with regard to coast-lines. . . . 



Terrible and striking, then, as are the 

 phenomena connected with volcanic action, 

 such sudden and violent manifestations of 

 the subterranean energy must not be re- 

 garded as the only, or indeed the chief, effects 

 which they produce. The internal forces 

 continually at work within the earth's crust 

 perform a series of most important functions 

 in connection with the economy of the globe, 

 and, were the action of these forces to die out, 

 our planet would soon cease to be fit for the 

 habitation of living beings. . . . 



It is by no means a difficult task to cal- 

 culate the approximate rate at which the 

 various continents and islands are being lev- 

 eled down, and such calculations prove that 

 in a very few millions of years the existing 

 forces operating upon the earth's surface 

 would reduce the whole of the land-masses to 

 the level of the ocean. . . . 



But, by the admirable balancing of the 



external and internal forces on our own 

 globe, the conditions necessary to animal and 

 vegetable existence are almost constant ly 

 maintained, and those interruptions of such 

 conditions, produced by hurricanes and 

 floods, by volcanic outbursts and earthquakes, 

 may safely be regarded as the insignificant 

 accidents of what is, on the whole, a verj 

 perfectly working piece of machinery. 



LITERARY NOTICES. 



The Ancient Bronze Implements, Weapons, 

 and Ornaments of Great Britain and 

 Ireland. By John Evans, D. C. L., 

 LL. D., F. R. S., F. S. A., F. G. S., Presi- 

 dent of the Numismatical Society, etc. 

 New York: D. Appleton & Co. 1881. 

 Pp. 509. Price, $5. 



A few years ago there appeared a portly 

 volume, profusely illustrated, and entitled 

 " The Ancient Stone Implements and Orna- 

 ments of Great Britain." It was a monu- 

 ment of careful observation and painstaking 

 labor in a new field, with not many enthusi- 

 astic explorers, and was at once accepted as 

 a trustworthy and authoritative work upon 

 the subject, which, although chiefly confined 

 to Great Britain, was an important contri- 

 bution to the general science of archaeology. 

 Mr. John Evans, the author of that work, has 

 continued to devote himself to the field of 

 archaic research, and now publishes a cor- 

 responding volume on " The Ancient Bronze 

 Implements, Weapons, and Ornaments of 

 Great Britain and Ireland." 



We have here a history more ancient 

 than written history, and which reveals the 

 social state, the conditions of culture and 

 development of prehistoric man. These 

 are determined by the evidences of what 

 he did, the relics that remained- and have 

 been found, of what he invented and con- 

 structed to meet his wants. His first tools 

 and weapons were of stone, and the period 

 when he employed them is the earliest of 

 which we have any trace, and is called the 

 " Stone Age." But there was an education 

 in these rude constructions which led to 

 progress, so that this most ancient period 

 has been divided into two stage-, the Palaeo- 

 lithic or the very earliest, and the Neolithic 

 or later stone age, which exhibits a marked 

 advancement in the art of producing stone 

 implements. 



