1885.] SAND-PLAINS OF BELGIUM. 275 



compared with what many may he ready to suppose. It may be 

 susceptible of demonstration by reasoning that the greatest depths of 

 the ocean hollows, to be measured by miles, feel the influence not 

 only of the tidal wave, but of every wavelet which pats lovingly tlie 

 the sandy beach, throwing off smilingly the radiance of the sun as 

 if waggishly courting his approval and wooing him to fun ; hut it 

 does not follow that the passage of even the tidal wave disturbs the 

 position of a single particle in the ocean bed in depths much less 

 profound than these. There are indications that even in lesser 

 depths tlian these the stillness is perfect. It is only on the shore 

 that the water of the wave rushes onward and seaward ; elsewhere 

 it rises and falls like the undulations of a ribbon shaken by the 

 hand ; and if so, little sand will be formed in the ocean's depths. 



On the other hand, there is constantly going on a transportation 

 of sand as well as of mud hy the rivers to the sea ; and in view of 

 this, we may conclude that the quantity of sand produced by the 

 action of the restless wave may be small compared with what may 

 have been supposed ; and the quantity borne into the ocean bed by 

 rivers, there to be spread out Ijy the diluvial action of the sea, is 

 great compared with what may have been thought probable. 



We seem to be getting on ; we are getting on, however, but 

 slowly. All that has been advanced may be satisfactory ; but the old 

 question returns in another form ; and that form is this, Whence 

 and how do the rivers obtain the sand which they convey to the 

 sea ? As it is with the sea, so is it with them : a portion of it 

 they make ; another portion of it, and that most probably a much 

 larger portion, they find ready made and only wash away. 



In regard to the time which may have passed while some of the 

 particles of quartz found in sand were being triturated and rounded. 

 Professor Kedzie, of the State Agricultural College in Michigan, 

 makes the following statement in an introduction to a lecture on 

 the Sands of Lake Michigan, the substance of which has been printed 

 as an Appendix to my volume on the Pine Plantations and the 

 Sand- Wastes of France : — 



"Few things in nature would seem less fitted to arouse the 

 imagination than a grain of sand ; but place the particles of sand 

 under a microscope and they stand out as beautiful quartz crystals, 

 only ground and rounded off into more or less spherical masses. 



" The proper form of a quartz crystal is a six-sided prism 

 terminated by six-faced pyramids. But in particles of sand these 

 angular faces have more or less completely disappeared, and a 

 rounded mass appears instead. The force which has ground these 

 particles of quartz into their more or less spherical form is the 

 attrition of the waves as they roll the particles of sand over each 



