BUREAU OF SOILS. . 159 



ered is over two and one-half times as large, and the work has cost 17 

 cents per square mile less than last year. The variation in the cost 

 per square mile is due in part to the character of tlie country, the con- 

 dition of the roads and of the weather, the complexity of the soils, 

 the presence and character of alkali in the Western areas, and the 

 accuracy of the base maps used. The average cost to the Depart- 

 ment of Agriculture of the work comj)lete, including supplies and 

 railroad ti-ansportation, the preparation of reports, and the salaries of 

 the men during the three winter months, when the field work has practi- 

 cally^ to be suspended, has been $2.81 per square mile, as against $3.26 

 per square mile last year, a saving of 45 cents per square mile. This 

 saving is due, not only to the greater efficiency of the field parties by 

 reason of their better training, but also to the longer average length of 

 tlie field season for each party, wliich has been accomplished by moving 

 the parties from place to place as the season advances. It has been 

 found possible to keep some of the parties out during the winter 

 in Arizona and southern California, and to shift parties working in 

 the Korthern States during the summer months to the Southern 

 States during the fall. In this way the average length of the field 

 season has been something over nine months ])er party, and it is 

 believed that this can be considerably increased, although it is advis- 

 able to have each party spend some time at headquarters, not only for 

 the final revision of their rej)orts and maps, but to get acquainted 

 with the office and laboratory work and to keep in close touch with 

 the objects and i^urpose of the soil survey. 



THE FIELD FORCE. 



The organization of the field force has been carried to a very high 

 state of efficiency. Administratively, the very greatest of care and 

 attention to details is given, and the low cost per square mile shown 

 in the preceding statements is due in a large measure to the judicious 

 and economical management of the force. The salaries of the soil 

 experts employed by the Bureau are low as compared with those 

 paid in other branches of scientific work. The expense of a party 

 of two men in the field for subsistence and the hire of a team aver- 

 ages about $120 per month, or $1,080 for the field season of nine 

 months. The parties are equipped with the most modern instruments 

 for the classification and survey of soils, and it has been possible to 

 furnish them with such explicit instructions as to the character of 

 their work, the subjects they are to investigate, and the subjects 

 which are to be discussed in their reports upon areas that they know 

 exactly what is to be done on entering a given area and can proceed 

 with their work with tlie minimum of time for preliminary investiga- 

 tions or reconnoissances. They are required to report to the central 

 office at least once each week, noting the area surveyed, the new soil 

 types established, and the character of their work; and to send in 

 from time to time sections of their map for criticism and sugges- 

 tion as the work proceeds. It is required that each party shall com- 

 plete the map in all details and write up the report in final shape 

 before leaving the area. The report is then tyiDcwritten, and a copy 

 returned to the field party for correction or for additions or changes. 

 The work of each party is thoroughly inspected, so far as this has been 

 possible, in order to correlate the new soil t3'pes with those already 

 established and to confer with the men as to suggestions which can 

 be safely made of new methods of cultivation or of new industries 

 which may be established. As the work of the soil survey assumes 

 greater proijortions, this inspection work becomes more and more 



