241 
1890-91.] Dr Murray and Mr Irvine on Silica in Seas. 
precipitated to the bottom when the river water mixes with the 
waters of the ocean.* 1 
We have consequently made a large number of experiments 
(exceeding 100 determinations) bearing on this point. The fol- 
lowing Table gives the results of a series of experiments with 
clayey matter suspended in sea-water of different salinities, and at 
different temperatures. 
Table II . — Amount of Clay remaining suspended in Sea-Waters 
of Various Densities , after being shaken up, and alloived to 
stand at rest , at Temperatures of 40° F. and 80° F. Results 
in grammes per Litre. 
a Temperature, 80° F. 
1025 s 
1026 s 
1027 s 
1028 s 
Time 24 hours, . . 
Sea Clay 
0-0038 
0-0033 
0-0033 
0-0028 
3 3 3 3 3 3 
Land ,, 
0-0033 
0-0023 
0-0023 
0-0023 
,, 120 ,, . . 
Sea ,, 
0-0003 
0-0003 
0-0003 
0-0003 
33 33 33 ' • 
Land ,, 
0-0003 
0-0003 
0-0003 
0-0003 
j3 Temperature, 40° to 50° F. 
1025 s 
1026 s 
1027 s 
1028 s 
Time 24 hours, . 
Sea Clay 
0-0058 
0-0063 
0-0068 
0-0068 
33 33 33 
Land ,, 
0-0058 
0-0060 
0-0068 
0'0060 
„ 106 ,, . . 
Sea ,, 
0-0013 
0-0018 
0-0018 
0-0018- 
J5 . 
Land ,, 
0-0015 
0-0013 
0-0015 
0-0013 
,, 120 ,, . . 
Sea ., 
o-ooio 
o-ooio 
0-0013 
0-0015 
>> 55 • ■ 
Land ,, 
o-ooio 
o-ooio 
o-ooio 
o-ooio 
y Temperature, 80° F. 
1000 s 
1005 s -6 
1010 s 
1015 s 
1020 s 
1025 s 
1028 s 
Time 24 hours, 
,, 96 „ 
0-0623 
0-0723 
0-0048 
0-0028 
0-0028 
0-0018 
0-0020 
0-0013 
0-0018 
0-0013 
0-0018 
o-ooio 
0-0018 
o-ooio 
* Advantage is taken of this fact in the purification of muddy waters for 
domestic and manufacturing purposes by adding lime and alumina salts, which 
induce the separation of suspended matter and its subsidence (see Sidell in 
Humphreys and Abbot’s Report on the Mississippi , Appendix A, Ho. 2, pp. 495 
etseq., 1876; Schultze, Pogg. Ann., vol. 129, p. 366, 1866). 
