REPORT OF THE SECRETARY. 109 



To carry out this work the department has stationed specialists in 

 various parts of the country, i:)articiilarly in the Southern and West- 

 ern States, whose services are available to communities, organizations, 

 and individuals who desire expert advice upon particular drainage 

 undertakings. Much of this service is of a consulting nature, but 

 where it seems desirable these representatives make detailed examina- 

 tions of concrete propositions, sometimes making complete surveys 

 and detailed plans, locating the drains upon the ground, and super- 

 vising the construction. These representatives also make inspections 

 of tile drainage sj^stems already installed, with a view to collecting re- 

 liable data as to their effectiveness under the conditions in which they 

 operate. Experimental Avork is carried on under varying conditions 

 of climate, rainfall, topography, and soil to determine the best practice 

 in such details as depth, spacing, and size of tile, effective measures 

 to prevent silting of drains, and the necessary provision for surface 

 run-off. In the arid regions the investigations are designed to meet 

 the peculiar problems presented by the rise of ground water, due to 

 irrigation and the resulting accumulation of alkali at the ground 

 surface. 



To the extent that time and means have permitted, the existing tile 

 drainage systems in southern Louisiana have been examined in the 

 endeavor to account for the almost universal ineffectiveness of tile 

 drainage that has hitherto obtained in that section. In every case it 

 was found that efficient drainage was precluded either by defective 

 design, faulty construction, or both. The attempt will be made in the 

 near future to overcome the prejudice that has naturally resulted 

 from those failures by supervising the installation of a number of 

 tile drainage svstems in that section. 



In Alabama an inspection has been made of all the existing tile 

 drainage systems in the prairie section. Four experimental tile 

 systems have been installed, and the results so far observed indicate 

 complete success of this method of draining where the system is 

 properly designed and constructed. 



The department has supervised the installation of a number of tile 

 systems in Georgia and the Carolinas which have been highly suc- 

 cessful in their operation. 



In Maryland, particularly on the Eastern Shore, and in Virginia 

 the service rendered by the department has resulted in an increasing 

 interest in agricultural drainage, several highly successful undertak- 

 ings of this nature having been carried to completion under the 

 supervision of the representative assigned to that territory. 



NUTRITION INVESTIGATIONS. 



Particular attention has been paid to studies of the use of corn 

 meal and its value in the diet in comparison with other cereals. On 

 the basis of data gathered from experiment and experience, a bulletin 



