ECONOMIC SURVEYS OF COUNTY HIGHWAY IMPROVEMENT. oY) : 
to three times the total cost of the improvements. The increase in 
values in those instances which were recorded ranged from 63 per 
cent to 80 per cent in Spotsylvania, from 68 to 194 in Dinwiddie, 
70 to 80 in Lee, 25 to 100 in Wise, 9 to 114 in Franklin, 50 to 100 in 
Dallas, 25 to 50 in Lauderdale, and from 50 to 100 in Manatee. It 
will be found upon reading the chapters on the individual counties 
that the estimates of increase were based for the most part upon the 
territory within a distance of one mile on each side of the roads 
improved. These estimates are not claimed to be mathematically 
exact, but itis believed that they will give a fairly accurate indication 
of the results which may be expected under similar conditions. 
In dealing with the effect of road improvement upon the hauling 
of commodities, the method has been adopted of ascertaining the 
traffic area served by each road much in the same manner as the 
drainage area of a stream is ascertained. After determining such 
areas the character and amount of production is ascertained and 
an estimate is made as to the proportion of the tonnage produced 
which is hauled upon the roads. A further investigation is made as 
to shipments by rail in and out of the county and information is 
obtained from United States census reports and from merchants 
and producers to verify the results obtained from the traffic-area 
calculation and the freight-tonnage inquiry. In some cases an 
actual traffic count or census is taken to determine the tonnage 
hauled upon the roads. From these various sources it is pos- 
sible to arrive at a reasonably accurate estimate of the tonnage 
hauled over the improved roads. It is a comparatively easy matter 
to determine the average length of haul in each case and the pre- 
vailing rate of wages for men and teams. With these factors the 
total tonnage, the total ton-mileage, and the cost per ton-mile 
before and after the improvement of the roads are computed. The 
saving to traffic represented by the road improvement is thus ex- 
pressed in doliars. It is of course realized that the figures given 
do not represent an actual “dollars and cents” saving, as many of 
the men and teams figured in on a wage basis might have been idle 
if they had not been engaged in hauling the products of farm and — 
forest. But they at least indicate the saving in time and energy, - 
and these have a monetary value. Therefore the saving to traffic 
in each county is stated for the purpose of indicating to the readers 
of this bulletin a relative figure by which they can determine the 
waste due to a system of poor roads. Considering the eight coun- 
ties in. the aggregate, the gross annual saving in hauling costs 
due to their good-roads systems affords the rather impressive total 
of $627,409 for a traffic of 3,489,652 ton-miles. The average gross 
saving per ton-mile for the eight counties is 17.8 cents, this being 
