330 ON THE MOVEMENTS OF THE EARTlfS CRUST. 



It is not my iutentioii to maintain that refrigeration Las not at all 

 coutribnted to give the surface of the earth the form which it now pos- 

 sesses. But I think that an auxiliary theory is required, which, while 

 it will not entirely supersede the old theory, may yet serve to explain 

 things which the old theory can not render comprehensible. 



Henry H. Howorth has written two memoirs, namely, " Eecent Ele- 

 vations of the Earth's Surface in the I^orthern Circumpolar Regions" 

 {Journ. Roy. Geogr. Soc, 1873, vol. XLiii, p. 240) and "Recent Changes 

 in the Southern Circumpolar Regions" {op. cit., 1874, vol. XLiv, p. 252), 

 in which he has brought together what was at that time known as to the 

 displacement of shore-lines in the last section of geological time, and the 

 principal result of his investigations is summed up in the following 

 words : " The South Pole, as well as the North, is a focus of protrusion, 

 the land around it is being gradually elevated." In the last section of 

 geological time, i. e., in the Post-glacial period, the land has in general 

 sunk under lower and risen under higher latitudes. 



Suess arrived at a similar result in his above-cited memoir {Verh. K. 

 K. Geol. Reiclis. 1880, pp. 174-175). He has likewise studied the dis- 

 placement of coast-lines over the whole earth during the period nearest 

 to the present time, and sums up the result as follows : " Terraced land 

 \i. e. land which has recently risen in relation to the sea] appears every- 

 ivhere in the highnorthern latitudes, so far as man has hitherto penetrated 

 into these solitudes. It also extends far, although not everywhere 

 equally far, down into the temperate latitudes, but generally decreasing 

 in height. In other words, around the North Pole, and far down, the 

 sum of the negative [i, e., descending] movements of the coast-lines is 

 greater than the positive; towards the south, however, these two sums 

 approximate more and more. In tropical seas, in the regions of the coral 

 formations, the opposite condition occurs, the sum of the positive move- 

 ments preponderates. Further towards the south, beyond 25^ to 35<^ 

 south latitud<\ the terraced land of the north begins again in South America, 

 South Africa, South Australia, and New Zealand, i. e., the same prepon- 

 derance of the negative movements, wn'th the same oscillating* charac- 

 ter as in the north." The exceptions (according to Suess) are few and 

 of little importance. 



Proc. Amer. Acad. Arts and Sci., 1873, vol. vili, p. 106), as also byO. Fisher ("Physics 

 of the Earth's Crust," 1881) and Dntton ("A Criticism upon the Contractioual Hypoth- 

 esis," iu Amer. Journ. Sei., 1874, ser. 3, vol. viii, pp. 113 et. seq.). They all consider 

 that contraction is not sufficient to explain the known phenomena; nay, the last- 

 named even thinks tliat the phenomena are opposed to this. A. de Lapparent, on the 

 other hand, in his memoir " Contraction et refroidissement du globe " {BulJ. Soc. Geol. 

 France, 1887, s6r. 3, vol. xv, pp. 383 et seq.) seeks to prove that they are quite suffi- 

 cient. 



* With this word Suess alludes to the circumstances that the coast-lines and terraces 

 occur at various levels one above the other. He thinks that each of these levels in- 

 dicates an oscillation of the sea. I believe that the tjreater part of these levels are 

 merely a consecjuence of climatic changes due to the precessions. (See Forh. Vid. 

 Sehk. Christ. 1881, No. 4.) 



