In the test of accuracy the following stages were carried out: 
1. 'The ground-profiles were drawn and compared with each other 
with the aim of ascertaining whether the differences between them 
were of such an order of magnitude that they might be conceived to 
affect the balancing as to height of the road-line. 
2. The cross-sections were drawn and compared with each other to 
ascertain whether the differences within the sections were of such an 
order of magnitude that they could affect the design of the roadbody. 
3. Mass calculation was performed with data from resp. measure- 
ments as a basis for an investigation of the differences in the masses 
(cut and fill). 
1. Fig. 9 shows the result from the first test with respect to the 
ground-profile for the first kilometer, 
From the result it can easily be seen that the accuracy of the ground- 
profile arrived at photogrammetrically is of the same class as that of 
the ground measurements, and the material may thus be used for the 
balancing of the road-line. 
2. Within the cross-sections there naturally occur certain deviations 
between the different measurements, due to the marked irregularities 
in the surface of the terrain. The selection of the measuring points with- 
in cross-sections and differences in the longitudinal measurement on the 
.ground in connection with the staking out of the sections give rise to 
differences in the result. The differences between the photogrammetric 
cross-sectioning material and measurement I are, however, of the same 
order of magnitude as the differences in the same material between 
measurement II and measurement I. Since for obvious reasons identi- 
cal points have not been chosen in the different measurements, the 
differences cannot be represented in figures. 
3. The mass calculation was performed with the help of the data- 
machine Facit EDB. In order to get a directly comparable idea of the 
differences in the mass calculation from the different measurements, 
the calculation was carried out with a type-section common for the 
entire stretch of road without any respect being paid to the nature of 
the ground. The balancing line used in the road project in practice was 
also employed in the test. The results of the test are given first in terms 
of a comparison with respect to masses between the different measure- 
ments in each section of cut and fill, see fig. 9 and then as a total for 
1 km and 2 km respectively. The result is shown in the table 1 below. 
The result shows that the material produced photogrammetrically has 
the same standard of accuracy as has the conventional measurement 
on the ground. 
To get an idea of the time spent and economy in connection with the 
utilization of photogrammetry, it may be mentioned that the instrument 
time for profiling and cross-sectioning of the two km in question 
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