434 Proceedings of the Royal Physical Society. 



and extension of experience in dealing with the crystals of 

 any given species, the shape of the several faces, or their 

 lustre, or their position between two faces already known, 

 etc., or any of these in combination, will usually sufl&ce 

 for determination by inspection. 



Of course, this kind of knowledge cannot be arrived at 

 without a considerable amount of previous work, or without 

 a very full and extensive knowledge of the general habit of 

 the species under consideration ; and it must be always borne 

 in mind that one observer may have gained this facility in 

 dealing with crystals of a certain species, or a small number 

 of species, and yet be quite unable at the outset to find his 

 way about the faces of the crystals of a species with which 

 he does not happen to be familiar. To do any really good 

 work in this, as in other lines of scientific work, one must 

 work long over a small number of species, and keep at the 

 work long enough to become more or less of a specialist. 

 I fear that there are, unfortunately, very few even of those 

 who are interested in Mineralogy who are willing to under- 

 take all the labour necessary even to obtain the requisite 

 knowledge of much more than the elements of Crystallo- 

 graphy. 



XXVIII. Obituary Notice of Mr James Bennie. By J. G. 

 GooDCHiLD, H.M. Geol. Survey, F.G.S., F.Z.S. 



(Read 17th April 1901.) 



It has not uncommonly happened that men who have 

 eventually attained to more or less eminence as geologists 

 have made a start in life under circumstances that might 

 appear to be altogether unfavourable for the development 

 of any scientific turn of mind. Many instances will im- 

 mediately occur to any one who will give the matter a 

 thought. The subject of this notice was not much more 

 favourably placed in this respect than others amongst those 

 just referred to. A brief sketch of his early career may 

 therefore suffice for the object at present in view. 



James Bennie was born in Glasgow in 1821. His health 

 as a child was not very robust, and his parents acted wisely 



