INTRODUCTION. 3 



chosen field of work, understanding that this is an age 

 of specialties, and that without devoting thought and 

 investigation to his particular pursuit he cannot expect 

 to be proficient in it. He should understand the drain- 

 age characteristics and capabilities of different soils, 

 and treat them according to their needs, keeping in 

 mind the ultimate use which is to be made of them. 

 The various means of accomplishing this work in the 

 most thorough and economical manner belong to his 

 special field of investigation and practice. There are 

 sound principles upon which drainage is founded, but 

 there are no *' standard plans" for accomplishing it, 

 as there are for the construction of many other kinds of 

 engineering work. Writers upon the subject of drain- 

 age frequently make a mistake along this line by recom- 

 mending certain plans and methods of work for all 

 localities without regard to differences of soil, climate, 

 physical conditions, or the use to which the land will 

 be put after it is drained. He who measures his skill 

 in drainage by his success with one piece of work in 

 one locality may easily flatter himself unduly, for the 

 reason that scarcely any two projects can be planned 

 and worked alike with equal success. 



There is a difference between the work of the sur- 

 veyor and that of the engineer, though both may be 

 done by the same person. The work of gathering defi- 

 nite data and facts and putting them in orderly form for 

 future use is strictly the work of the surveyor. He 

 may do all this and not have the requisite skill to use 

 the data thus obtained in designing and laying out an 

 effective and economical drainage system. The sur- 

 veyor secures data; the engineer plans and executes 



