758 THE SAM-LAKE OF LAKNACA. [Nov. I9OO. 



(19) Density of the Water. 



Some interesting particulars regarding the water in the salt-lake, 

 for which I am indebted to Dr. Otto Maas, are here appended : — 



The density of the water in the lake was taken on December 19th, 

 1899, and was found to be between 10°*5 and 11° by hydrometer 

 (areometer). The temperature of the water was 16 o, 50 Centigr. 

 (61°-70 Fahr.), and of the air 15° Centigr. (59° Fahr.) at the time. 

 This will be better understood when it is explained that the normal 

 density of the Mediterranean is between 3°-35 and 3 o, 40 by the 

 same instrument. 



On October 20th, 1899, towards the close of the hot season and 

 after only one shower of rain had fallen, the water was of too great 

 a density to be recorded by the hydrometer. On the 28th of the 

 same month, after heavy rain had fallen on two occasions, the 

 density was found to be about 17° or rather less. On December 

 29th, heavy rain having fallen on the 23rd and 24th, the density 

 was found to be 10°-2 and the temperature 14 0, 3 Centigr. On this 

 latter date also the water rising through the borehole driven on the 

 19th of the same month was found to be of 8°*2 density. 



(20) General Summary. 



The following is a summary of the observations recently made : — 



(i) The surface of the salt-lake, at what may be considered to be 

 its winter-level, is 7 feet, and the bottom of the lake is 10 feet 

 below sea-level. 



(ii) The sea-water percolates through the soil between the upper 

 surface of an impermeable stratum of indurated clay and the lower 

 surface of a bed of sandy clay of a less impermeable nature ; it 

 filters through this latter stratum, rising to the surface to 

 accumulate in a depression in the ground, and forms the salt-lake. 



(hi) The subsoil salt-water (which rose to the surface of the 

 lake-shore through the borehole recently driven) is of more than 

 twice the normal density of the sea, and about 75 per cent, that of 

 the water in the lake at the time of observation. 



(iv) The bottom of the salt-lake is covered with an incrustation 

 of salt overlying a layer of mud, consisting of the decaying remains 

 of micro-organisms and mineral matter. 



It is in conclusion the writer's pleasing duty to record his sense 

 of obligation to Dr. Otto Maas, whose valuable assistance has con- 

 tributed so largely to the preparation of the foregoing paper. 



PLATE XXXIX. 



Map of the Larnaca salt-lake and its immediate neighbourhood, 

 on the scale of one inch to the mile. 



