2i6 Forestry Quarterly. 



quent intervals, and should be placed in the office files instead 

 of being carried by the investigator until he is ready to submit 

 a complete report. Field data should be compiled from time to 

 time by the man who gathers them. If they are left in rough 

 form until the end of the season when a report of the year's 

 work is due and when the original collector may have gone, the 

 man who prepares the report will find himself confronted by a 

 formidable task, to say nothing of the loss from his inability to 

 interpret another's notes. The original field notes should be filed 

 with the compiled results. They are often of value in checking 

 errors and in clarifying various perplexing problems. 



The director should examine and correlate the data on each 

 project sufficiently often to keep in touch with all developments. 

 In addition to this, he should make frequent inspections on the 

 ground, particularly if the work is being conducted by inexper- 

 ienced men. This is necessary not so much for the purpose of 

 checking the accuracy of his assistants' work as to check their 

 judgment and to observe facts which may have escaped their 

 notice. Many instances could be cited where absolute reliance 

 on the data gathered by assistants, though accurate and in ac- 

 cordance with instructions, would have resulted in overlooking 

 important facts, the omission of which might have materially 

 changed the conclusions. No investigator can foresee all the 

 factors which may enter into an experiment, and consequently 

 he can not prepare instructions sufficiently complete to cover 

 all points. The highest type of scientific work is done by scien- 

 tists who, if they can not actually perform all the work them- 

 selves, personally supervise all important details. 



While the preceding paragraph shows the inadequacy of in- 

 structions unaccompanied by thorough inspection, it is by no 

 means the intention to belittle the value of detailed instructions. 

 Fortunately the Forest Service now requires that a working plan 

 be prepared for every experiment before the work is begun. 

 The value of the plan is not so much in guarding against im- 

 proper methods of study as in the assurance that a plan of work 

 is actually made. The working plan should cover every detail, 

 if for no other reason than that it requires the investigator to 

 think out these details in advance. A complete plan is especially 

 valuable when the responsibility for the project is delegated 

 temporarily or permanently to an assistant. If the director of 



