To determine the relationships between moisture contents and soil densities under a standard method of compaction and also the effects of these moisture contents on the ability of the soil to resist penetration. Two types of compaction tests are routinely performed: (1) The Standard Proctor Test, and (2) The Modified Proctor Test. Each of these tests can be performed in three different methods as outlined in the attached Table 1. In the Standard Proctor Test, the soil is compacted by a 5.5 lb hammer falling a distance of one foot into a soil filled mold. The mold is filled with three equal layers of soil, and each layer is subjected to 25 drops of the hammer. The Modified Proctor Test is identical to the Standard Proctor Test except it employs, A 10 lb hammer falling a distance of 18 inches, and uses five equal layers of soil instead of three. There are two types of compaction molds used for testing: The smaller type is 4 inches in diameter and has a volume of about 1/30 ft3 (944 cm3) and the larger type is 6 inches in diameter and has a volume of about 1/13.333 ft3 (2123 cm3). If the larger mold is used each soil layer must receive 56 blows instead of 25.