MR. STRANGWAY’S ALLUVIUM AND DILUVIUM IN RUSSIA. 18? 
The difference between the two species of alluvium thus clearly 
pointed out by Mr. Bald, as prevailing in Scotland, is the same which 
I have stated to exist universally over the world; and for the purpose 
of distinguishing which, I have, in my table of the super-position of 
the strata in the British islands, proposed to limit the term alluvial 
to those partial deposits which Mr. Bald calls “ recent alluvial covers,” 
the origin of which may be referred to the daily action of torrents, 
rivers, and lakes; and to appropriate the term diluvium to those 
universal deposits of gravel and loam which he calls “ the old alluvial 
covers,” to the production of which no cause at present in action is 
adequate, and which can only be referred to the waters of a sudden 
and transient deluge *. 
* The Hon. Wm. Strangways, in a valuable Synoptic Table of the Formations near 
Petersburg, published by him during his late residence in that city, has adopted the di¬ 
vision I am now speaking of between diluvian and postdiluvian formations; distinguishing 
them by the name of diluvium and alluvium. He dates the commencement of the allu¬ 
vium from the period of the retreat of the last waters that have covered the earth, and 
includes under it—1, Drift sand; marine, or inland; 2 , Marsh land; composed of mud 
deposited by rivers; 3, Peat; 4, Calcareous tuf. All these formations are referable to 
causes that are still in daily action. Under the term diluvium he includes the superficial 
gravel beds that lie indiscriminately on all strata of antediluvian origin, and are composed 
of a mixed detritus of pebbles, sand, and clay, torn down from formations of all ages, 
except alluvial; and also the blocks of granite and other fragments of primitive and 
secondary rocks, that are scattered over the plains and low hills of that part of the north 
of Europe, either mixed with the superficial gravel, or lying insulated in situations to which 
they must have been drifted from very considerable distances, as there is no matrix near 
them from which they could by possibility have been derived. He has omitted to men¬ 
tion beds of gravel produced locally by torrents and rapid rivers, because the flat con¬ 
dition of the district on which his synoptic table is founded has allowed no gravel of this 
kind to be transported to so great a distance from the hills or mountains, from the daily 
detritus of which it is immediately derived. 
A well digested and valuable comparative account of the mode of action and effect 
B B 2 
