ACKROYI) : OX THE CIRCULATION OF SALT. 
417 
uncommon thing for Palestine to be drenched with sea-salt by the 
prevalent westerly gales, in which case a more important contri- 
bution towards the saltness of the Dead Sea would be made than 
could be furnished by its widely-distributed limestone rocks. On 
this subject I hope to get definite facts from the analyses of Palestine 
limestones. Through the kind offices of one of our Vice-Presidents 
(Mr. Walter Morrison) a number of samples have been submitted 
to me for this purpose by the Palestine Exploration Committee. 
In opposition to this view it has been pointed out that wide differences 
exist in the composition of the waters of salt lakes, and the opinion 
has been expressed by Professor Joly* that " the whole facts of the 
case entirely negative the wide deductions," which I have founded 
on my calculations. He further says : " The very variable composition 
of salt lakes must be regarded surely as an insuperable objection. 
. . . ! The Dead Sea, for instance, shows a very large excess 
of magnesium salts over sodium salts, the chlorides constituting 
lo'O per cent, and per cent, respectively of the total solids. There 
is even a large excess of calcium over sodium in its waters. In the 
Great Salt Lake the proportions are just the other way. The per- 
centages are nearly marine. 11-9 per cent, of sodium chloride and 
a very little magnesium chloride, but l"! per cent. There is relatively 
very little calcium. . . . Thus, the lake which is most favourably 
situated for the rain supply of sea-salts is just that one which most 
completely departs in its chemical composition from that of the ocean. 
Again, we find a lake, such as the Elton Lake of the Kirghis Steppe, 
200 miles from the Caspian, possessing a chemical composition ap- 
proximating to that of the Dead Sea — 19*7 per cent. MgCl2, 5-3 
per cent, of MgSO^, and 3*8 per cent. NaCl. Calcium is, however, 
in its case absent or inappreciable." {Chemical Neius, June 28th, 
1901, p. 301.) 
These seeming discrepancies disappear in the light of a principle 
which I enunciated recently {Geological Magazine, Decade lY, Vol. 
* The controversy on these matters between Prof. Joly and myself will 
be found in the Chemical News, June 28th and August 2nd, and Geological 
Magazine for August, October, November, and December, 1901. 
