Abstract
The composition of traffic on the Arterial Roads in Ireland was recorded by taking a one day visual census in July, 1968 at 145 points on the network. Eight classes of vehicle were identified and the results are presented in tabular form by vehicle class and by time of day. The census points included 45 locations where self-recording mechanical counters are permanently installed. The report compares the results from the visual census with the simultaneous output from the self-recording counters and comments on the sources of counter error. Recommendations are made in relation to future census of this nature.