440 



TABLE 454.— DIELECTRIC CONSTANT AND LOSS TANGENT OF DIELECTRIC 



MATERIALS (concluded) 



1% antioxidant (Bakelite). 24, 100% polyvinyl chloride (Bakelite). 25, Polyvinylidene and vinyl chlorides 



(Dow). 26, Polymethyl methacrylate (DuPont). 27, For sheet stock, various samples used for different 



frequencies; for rod stock, e'Ao is the same as for sheet stock. (Plax). 28, Pale crepe (Rubber Research 



Corp.). 29, Palaquium Oblongifolium (Hermann Weber). 30, 100 pts GR-S, 1 pt stearic acid, 5 pts 



Kadox, 5 pts Captax, 3 pts sulfur (Rubber Research Corp). 31, Copolymer of 98-99% isobutylene, 1-2% 



isoprene (Rubber Research Corp.). 32,Poly-2-chlorobutadiene-l, 3 stabilized with Methyl Tuads (DuPont). 



33, Fossil resin (Amber Mines). 34, Contains ca. 3.5% wax (Zinsser). 35, Central Scientific. 36, 



Shell Oil. 37, Bromund. 38, Vegetable and mineral waxes (Kuhne-Libby). 39, Mainly C22 to C29 



aliphatic, saturated hydrocarbons (Standard Oil New Jersey). 40, Dennison. 41, Research Laboratory 



of Physical Chemistry, Massachusetts Inst. Techn. 42, Absolute, Analytical Grade (Mallinckrodt). 43, 



Absolute (U. S. Industrial Chemicals). 44, Eastman Kodak. Dried and refractionated, Lab. Ins. Res. 



45, Purified Lab. Ins. Res. 46, Dow. 47, 72.0% paraffins, 28.0% naphtlienes (Stanco). 48, 57.4% par- 



affins, 42.6% naphthenes (Stanco). 49, 72.4% paraffins, 27.6% naphthenes (Stanco). 50, 49.4% paraffins, 



50.6% naphthenes (Stanco). 51, Aliphatic and aromatic hydrocarbons (General Electric). 52, Chlorinated 



benzenes and diphenyls (General Electric). 53, 60% mono-, 40% di- and trichloronaphthalenes (Bakelite). 



54, Methyl or ethyl siloxane polymer (Dow Corning). 

 cs., centistoke. 



TABLE 455.— DIELECTRIC CONSTANT AND CONDUCTIVITY OF SOILS" 2 



Measurements of samples of soil taken from different depths at various sites in England 



Geological 

 classification 



Lower 

 lias 



Chalk 



Upper 

 greensand 



Depth 

 ft 



Description 

 of sample 



Moisture 



content % 



by weight 1 kc 



Conductivity (in esu) at 20°C 



100 kc 



1.2 Mc 10 Mc 



Upper 

 lias . 



Red marls. 



Devonian 



Granite . . 



Boulder 

 clay . . . 



Surface Dark fibrous loam .. . 60 3.0X10 8 



1 Loam and clay 33 6.5 



2 Clay and sand 26 7.5 



3 Blue clay 25 8.0 



Surface Fibrous loam . , 21 .85 



1 Chalky loam 21 .55 



2 Chalk 24 .28 



Surface Fibrous loam 37 2.7 



1 Brown, sandy clay.. 19 2.2 



2 Brown sand 15 1.8 



Surface Fibrous loam 28 .85 



1 Sandy loam 16 .34 



2 Brown sand 14 .29 



5 Sand and sandstone . . 8.5 .075 



Surface Reddish-brown loam. 23 1.5 



1 Reddish-brown clay. 20 1.5 



2 Reddish-brown clay. 18 2.6 



Surface Black fibrous loam.. 21 1.3 



1 Loam and slate 9.0 .026 



10 Slate — .00026 



1 Gritty loam 18 .12 



3 to 10 Granite — .00090 



3 to 10 Granite — .00070 



Surface Fibrous loam 38 .55 



2 Clay and loam 19 1.1 



3 Dark grit and clay.. 18 .60 



3.4X10 8 3.9X10 8 6.0X10 8 100 



7.0 7.0 9.0 95 



8.0 8.0 12.0 105 



9.0 9.5 11.0 95 



.90 

 .55 

 .26 



3.4 

 2.4 

 2.0 



.95 

 .34 

 .29 

 .090 



1.7 

 1.7 

 2.S 



1.5 

 .030 

 .0025 



.12 



.0070 



.0050 



.65 

 1.1 

 .70 



.95 

 .85 

 .38 



4.0 

 2.4 

 2.1 



1.1 

 .40 

 .33 

 .12 



1.8 

 1.8 

 3.1 



1.4 

 .95 

 .61 



5.0 

 3.8 

 3.3 



1.6 

 .61 

 .46 

 .22 



2.3 

 2.5 

 3.6 



39 

 41 

 28 



80 

 39 

 33 



46 

 50 

 80 



8 2 5 

 O40 .060 

 0092 .046 



.16 



.028 



.019 



.75 

 1.2 

 .80 



.18 

 .11 

 .095 



1.1 

 1.7 

 1.2 



50 

 60 

 50 



23 

 25 

 21 



49 

 19 

 19 



48 30 



20 17 



20 14 



14 9 



32 

 33 



45 



90 65 



12 10 

 9.5 8.0 



22 15 

 12 8.5 

 10.0 7.5 



20 

 21 

 19 



152 Smith-Rose, Journ. Inst. Electr. Eng., London, vol. 75, p. 221, 1934. 



SMITHSONIAN PHYSICAL TABLES 



