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Highway engineers know only too little about the state of their roads, and the apparatus and methods described in the Paper for the routine assessment of their condition should be of the utmost value and have come at a very timely moment when closer attention than ever before is being directed to highway maintenance programmes.64. The Marshal1 Committee referred to the need for greater precision in forecasting maintenance requirements, and these can be obtained by the methods described by the Authors. My Department was no exception and we realized that the information in our possession about the strength and surface qualities of our trunk roads left something to be desired. This was quite evident from the adjustments which have to be made during the year to our annual maintenance programmes to deal with unexpected occurrences and occasional failures. For some years past we have employed the Benkelman beam to test for strength of pavements and the pendulum tester to measure skidding resistance. The Benkelman beam has proved a most useful tool and has enabled major maintenance works to be carried out in a most economical manner.65. Examples which come to mind: on the M1 it told us with reasonable accuracy the areas where foundations needed to be replaced. On the Stamford by-pass it told us of the thicknesses of overlay required to provide the necessary strength of pavement. Without the beam I think it very probable that in both these cases we would have overdesigned with considerable loss of economy. There is obviously a clear need for more apparatus of this kind. 66.The pendulum tester has, however, not been nearly so useful and, as the Authors point out, it needs considerable skill to interpret the results. The result of this has been that it has tended to be carefully locked away in various offices of the Department.67. Both machines suffer severe limitations in use. They are slow in operation and are difficult to use on high speed roads, as personnel obviously have to be protected adequately from traffic. Neither can be used without a great deal of advance preparation. Sufficient lessons have, however, been learned from these machines to make it clear that substantial improvements in the economy and efficiency of our maintenance programme might well be practicable if better apparatus can be made available. The development of the SCRIM and deflectograph machines which might do just that is, therefore, particularly welcome. We are, therefore, in process of setting up a unit called the Road Surface and Strength Testing Unit which will have the job of assessing the effectiveness of operation of these machines in normal operational usage and of establishing whether they will lead to improved standards of skidding resistance and pavement maintenance thereby permitting the more effective use of available funds. Initially, at any rate, the unit will be operating in our SouthEastern Division, and a provisional plan has been drawn up for its work during the coming summer. This unit will work in very close conjunction wi...