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total of five percent, is normally considered essential to cover adequate fea 
sibility studies which include studies of communications and other factors 
which are relevant to this symposium since, frequently aerial survey techniques 
are involved. Before leaving this question of capital requirements, one point 
should be stressed, and that is the necessity for this type of pre-investment 
survey to obtain all possible information on all relevant aspects, not merely 
the raw material supplies, potential markets and “other factors”, but also an 
assessment of the position such a project may have in the general economic 
development of a country. Nowhere is this more important than in the devel 
oping countries, where capital investment can play a great part in economic 
growth and in fostering other investments such as improved housing, com 
munications, health services, power and water supplies. All the facts should 
be to hand on which the government of the country concerned can either make 
investment decisions itself or negotiate equitable terms with commercial in 
terests. By setting out the pros and cons for each project for which a pre-invest 
ment survey is carried out, these factors can be thoroughly analysed, critically 
appraised, and clear cut recommendations made. Alternatives need to be 
examined and cost estimates for the various alternative proposals prepared. 
As mentioned before this should, in general, raise the pre-investment survey 
cost to approximately live percent of the ultimate investment cost. For this 
expenditure the parties meeting the resource appraisal cost would know not 
only whether they have a viable project, but they would also have an accurate 
assessment of the cost required to implement the project and its probable 
return, with alternatives, on the basis of certain projections. These forecasts, 
particularly growth and demand forecasts, may be subject to error, but they 
can be phased to give indicators at certain target dates which will serve as a 
control for the projections of the whole pre-investment survey. 
Communications 
The next important factor to consider is communications. This applies not 
only to the movement of raw material supplies but also to the transport of the 
finished products. For example, when carrying out a forest inventory it is 
extremely important to know the nature of the terrain and the difficulties 
which are likely to be involved in extracting timber from the area being 
surveyed. Much of this information can be obtained by preparing accurate 
topographic maps for areas already known, from the forest inventory results, 
to contain exploitable stands of timber. There is little point in making accurate 
topographic maps of a whole project area unless one knows that the raw 
material supplies are there. Then, on the basis of the preliminary maps made 
in the course of the forest inventory, an accurate topographic mapping pro 
gram can be undertaken. By having aerial photography flown to a suitable 
specification it is possible to use this photography both for photo interpretation 
purposes and for accurate topographic mapping. Such maps can of course 
easily be made by the use of modern photogrammetric plotting instruments. 
What is often not appreciated by the photogrammetrist, and sends shudders