478 Mr. 0. Tomlinson on the Weathering of Rocks, 



fused way; and the slopes of many of the hills are strewn 

 with them, while the summits are formed of layers broken up 

 into separate blocks by weathering. Some of these weathered 

 blocks resemble ruined masonry. Mr. Stow says that in the 

 Kolberg " these shales have been denuded into a remarkably 

 shaped shoulder, jutting out, like the front of a portico, from 

 the mountain-side. They appear to have been left perfectly 

 undisturbed upon the more ancient rocks forming the prin- 

 cipal part of the mountain. These latter rocks rise on each 

 side into kopjes sixty feet high. Signs of stratification may 

 be seen very distinctly in the hill to the left. Here two of 

 the layers have weathered until their surfaces have assumed 

 a rude columnar appearance. The parts above these, and 

 also those which cap the other kopjes, are composed of rather 

 more coarsely crystalline rocks. They also show lines of 

 stratification ; but, instead of the columnar appearance just 

 mentioned, they cleave into immense blocks, piled one on 

 the other, and looking in many places like Cyclopean walls 

 flanking the lops of the hills."* 



It appears from the above details that Mr. Haggard, seeing 

 the weathered mason-like blocks of the hills, supposed them to 

 be built up from the rounded boulders of the older boulder- 

 bed. The old boulder-clay is 1200 feet thick; the boulders 

 are smooth, but are not rounded "like cricket-balls ;" and in 

 weathering or failing-out into the valleys they are often piled 

 one on the other to no great height, and they are kept in 

 place by mutual lateral support. The largest are rarely more 

 than six feet across ; in short, there is nothing that can give 

 any sanction to the statement that in the Transvaal there are 

 columns formed of ball-shaped boulders which have been 

 rounded by the action of water, and which have subsequently 

 been balanced one on the other. The statement is altogether 

 misleading, and therefore mischievous, and yet this writer 

 persists in it to the end ; for at page 330 we read : — " The 

 moon's first rays lit upon one of the extraordinary pillars of 

 balanced boulders." 



In connexion with our present subject may be mentioned 

 a remarkable example of science correcting the views of the 

 antiquaries of the last century, who expended much labour 

 in endeavouring to prove that the rocking stones of Cornwall 

 are Druidical monuments, whereas they are simple cases of 

 weathering. Dr. Paris j many years ago, in describing the 

 Logan or Logging-stone near the Land's End, states that the 



* "Notes upon Griqua Land West," Quart. Journ. Geol. Soc. xxx. 

 p. 588 (1874). 



t Philosophy in Sport, &c. 



