THE NETHERLANDS-EAST-INDIES. 25 



If the course of a river has to be sketched, it should be done 

 when travelling up-stream, because in the opposite direction the 

 speed is as a rule too great for accuracy. Such surveys are very 

 inaccurate, even after long practice, and should if possible in any 

 way be used between some points, the situation of which is 

 already known. 



12. COSTS. 



These are very difficult to estimate; first because the means of 

 communication are frequently modified, secondly because the per- 

 sonal element plays an important part in the work and thirdly be- 

 cause the purpose for which one is travelling makes a great difference. 



The time-table of the K.P. M. (Royal Packet Company) contain 

 the fares of transportation. The wages of the helpers differ very 

 much according to the part to be traversed and also according to 

 the season. To get a notion of it, 2/6 per man and per day should 

 be reckoned, food included. For inhabitants of the district this 

 amount suffices, but it will increase if the men have to be brought 

 from elsewhere, as is the case for expeditions in New Guinea 

 (For more informations see the reports on them, a.o. in the Journal 

 of the Royal Dutch Geographical Society). 



