412 Trof. T. G. Bonney and Miss Raisin — 



sufficient evidence to found a case adverse to the generally received 

 theory of production of saline deposits. I gather that, notwith- 

 standing what is now advanced, the case is still incomplete, yet 

 I trust Mr. Middlemiss will follow up the subject to conclusions 

 that cannot be called hypothetical, and maj'' effectively reconcile 

 several obscurities on both sides of the Indus. 



When I was at the Salt Eange, the facts of internal lateral thrust 

 displacements not having been demonstrated, it was plain the series 

 must have been laid down upon something, and the marl occupied 

 the place of the visible floor to the rest. Supposing the part above 

 to have been unconformably deposited, what conditions would have 

 preserved a soft saline marly mass to have received later accumu- 

 lations ? But if it was found Immediately succeeded by earthy 

 layers passing up into sandstones, the main conditions for tranquil 

 sequence would seem to have been present as I saw the sections. 

 I have not seen the brecciated junctions of the Purple sandstone 

 with the underlying marl as described in the paper, nor do I quite 

 grasp how such a condition — not merely superficial, but the result 

 of deep friction — might be established between substances like 

 soft ' scum ' and hard sandstone. This, of course, is said with 

 reserve, and subject to correction by students of earth-movements, 

 thrusting, and so forth, which I have not had the advantage of 

 working out in natural exposures. 



While greatly interested in Mr. Middlemiss's frank, able, and 

 lucid contribution to the literature of the Salt Eange, I am yet 

 fain to hope that — aside from subsequent revelations in structural 

 geology — other readers of my memoir will find most of its con- 

 clusions reasonable at the time it was written. Our knowledge 

 is happily progressive, and considering the extent of the region 

 itself, with the circumstances governing its exploration, I can scarcely 

 feel vain regret that something did, or may still, remain to be dis- 

 covered. On the contrary, few will learn with greater satisfaction of 

 solid additions or improvements to what has been already ascertained, 

 notwithstanding that the results, such as they were, which attended 

 my labours for rather more than two working seasons, cost me a 

 good deal of thought and exertion, with serious loss of health, and 

 consequently of my employment — considerations, however, already 

 amply recognized as having nothing whatever to do with the geology 

 of the Salt Eange or other regions. Nevertheless, the retrospective 

 pleasure of appreciating the observations of later investigators made 

 upon the spot, must still remain possible to an old field-geologist 

 like myself. 



Kingstown, 2Zrd July, 1891. 



VI. — Eeport on some Eock-Specimens from the Kimberlet 



Diamond-Mines. 



By Prof. T. G. Bonney, D.Sc, LL.D., F.R.S., F.G.S., 



and Miss C. A. Eaisin, B.Sc. 



[From a collection of stones obtained from the refuse-heaps of 



the Kimberley Mines by Mr. Louis Atkinson, a selection was made 



