In concluding the session, the Chairman stated that he felt BrigadierHotine was a little pessimistic as to the accuracy obtainable. While he agreed that the accuracy mentioned was that which might be obtainable by a single set of observations, in which no special allowance was made for local atmospheric conditions, he was quite sure that by a series of flights across the base line, and by allowance for atmospheric variation, the accuracy of measurement of long lines could consistently be much better, and in fact this appeared to be already confirmed by results.