J. G. WALLER ON SAND. G3 



thesis must stand by itself. But there is one point worthy of note, 

 wherein he speaks of the extremely minute particles produced by 

 mere attrition. This in rounded pebbles must indeed be infini- 

 tesimal, and one could hardly expect to find such particles of any 

 moment in the composition of sand. But it must be otherwise 

 with the rough flint, as it comes from the chalk, and doubtless such 

 sand particles of this material, which are found, are thus produced 

 before the pebble is softened into a rounded form. 



It would certainly be plausible, as has been suggested, that a 

 molecular change may take place in flint during the lapse of ages, 

 difference of temperature, and the like. But the fact that flint 

 particles do appear, although in small quantities, in ancient deposits, 

 exactly the same as you may now artificially produce them, deprives 

 us of the use of such an argument. Its great scarcity, as I have 

 shown you, almost seems illogical, but the sternness of our facts 

 makes us accept them whether we like it or not, and we must endea- 

 vour to explain this phenomenon by the same logic of facts. But 

 the ubiquity of quartz sand is not confined to our coast. In exa- 

 mining some organisms from South Australia, containing sandy par- 

 ticles, some also from Mauritius, Madagascar, and Algoa Bay, 

 the same facts are shown. There are not only the common quartz 

 grains, but other materials, such as are visible among the sandy 

 deposits I have described, and seen in about the same proportion. 

 This is interesting, as declaring one universal source, whether in the 

 northern or southern hemisphere, and helps in the illustration, if not 

 in the solution of the question before us. 



I must confess to ignorance of many points of detail suggested 

 in this inquiry, but as we are composed of many active units, let us 

 take a moral from a grain of sand, one of the smallest of atoms, 

 yet in its aggregate playing so great a part in this earth's crust. 

 Let, then, the aggregation of our Society's units make a large addi- 

 tion to our scientific knowledge ; the subject before you has yet 

 many lapses, and I trust these may be filled up by your active 

 researches. 



The following is an analysis of the sands of the Tertiary 

 system : — 



BEDS OF SAND. TERTIARY SYSTEM. 



1. London Clay. Alum Bay. 



2. Top of London Clay. White Cliff Bay. 



3. Top of London Clay. Alum Bay. 



