394 Joty—Some Sedimentation Experiments and Theories. 
TABLE I. 
Rate or Compactrine. 
5 Grammes Slate Powder in 12 c.cs. Liquid. 
Minutes Depression of Surface of Sediment 
tan ean eewe Appearance of Liquid 
0 First Second Third above Sediment. 
Settlement. | Settlement. Settlement. Settlement. 
NaCl 10 1:3 1-1 0:9 
0:90 gramme 20 2°6 2°2 2:1 NO 
equivalents 30 3°6 3:2 3:0 CON Vie bres 
per litre. 40 5'6 4:2 4:2 
10 1:3 11 0-9 aj 
Fee 20 ey an ee 2-15 
0:45 gramme 30 3-6 | 3-4 3-9 As above. 
equivalents. > 40 57 | 45 fol 
10 1:4 igh | OF 
see 20 Oe | ORB 2-1 
0-225 gramme 30 3-9 3-4 3.9 As above. 
equivalents. | 40 5:9 Ad 4:3 
NaCl | 5 oe ae ee Not quite so 
0:112 gramme | 30 3-4 9-9 | 2.7 limpid as the 
equivalents. 40 52 3.9 | 3.7 above. 
NaCl a se oe Hee A little less 
0:056 gramme 30 3.7 | 9:8 2-7 translucent than 
equivalents. 40 i | "40 3-7 last. 
NaCl oy 5 a ee inant as 
0-028 gramme 30 3.9 2-6 O-5 translucent as 
equivalents. 40 a0 3-6 3-3 paraffin wax. 
NaCl a ae ae ue Muddy, but 
0:014 gramme 30 3.7 3.0 2:8 more translucent 
equivalents. 40 ited 4:9 3.7 than tallow. 
ty 10 1-1 2 2 
NaCl eS ae o) 0) ie Very muddy, 
0.007 gramme 30 32 | 8-0(2) (2) appearance of 
equivalents. 40 car | Ac) () tallow. 
Table II. shows that a diad positive ion is more effective than a monad 
positive ion; producing not only a slightly increased rate of settlement but 
preserving a sediment-surface under conditions when the monad ion would prove 
ineffective. 
