52 T. LytTTLETON Lyon AND JAMES A. BizZELL 
Volume weight | 
Before the soil was placed in the tanks all stones larger than a walnut 
were removed from it, but, as is characteristic of this soil series, a large 
number of small stones still remained. It is probably on this account 
that the volume weight of the soi! was so high. The weight of each 
twelve-inch layer of air-dry soil placed in the tanks is shown in table 1: 
TABLE 1. AveracE Wercut or Eacu Twetve-IncH LAYER OF Sort IN TANKS 
| 
First Second Third Fourth 
foot foot foot foot 
(pounds) (pounds) (pounds) (pounds) 
Weight of soil in tanks............... 2,250 2,170 1,850 es 
Weichtiol-soiliperiacre: 2 ..22 221s. a1 5,625,000 | 5,425,000 | 4,625,000 | 4,375,00 
This, it may be remarked, is a soil having greater volume weight thar 
the Dunkirk clay loam used in tanks 1 to 12 inclusive, owing, in pari 
at least, to the large number of stones. 
Mechanical composition 
A statement of the mechanical analysis of the soil by the centrifuga 
method, including all particles from fine gravel to clay, is given in table 2 
TABLE 2. MercHanicAL CoMPosITION OF SOIL IN FIELD FROM WuicH Tanxs 13 To IP 
WerReE FILLED 
First Second Third Fourth 
Separates foot foot foot foot 
(per cent) | (per cent) | (per cent) | (per cent. 
Hinetgravelt Bee Aneesh nae ee ee 2.32 5.32 3.00 5. 
@oarse'sand it) 24x or es ee eee 2.91 4.83 2.78 Sy. 
IMediumysand!; esse ne eee eee 3.02 4.64 2.85 oy 
BNE Sass fet ee = ee oh ee pees ore ee 6.32 8.60 6.30 9. 
Mery: fine sand): “15ers 08 enh es ete eee 15.92 18.22 15.80 14. 
oy Cigale te on eedtes. Mit eae Rae rue uate a ree 50.88 42.60 a SOF 39. 
Claeys Sola ae CC ot gaint ep eee 18.63 16.79 18.02 20: 
