The very hansom which bore me from the Temple to Kennington Lane was utilized for a preliminary test of Thorndyke's little apparatus.

During the whole of that brief journey I watched the compass closely, noted the feel and sound of the road-material and timed the trotting of the horse.

And the result was quite encouraging.

It is true that the compass-needle oscillated wildly to the vibration of the cab, but still its oscillations took place around a definite point which was the average direction, and it was evident to me that the data it furnished were very fairly reliable.

I felt very little doubt, after the preliminary trial, as to my being able to produce a moderately intelligible track-chart if only I should get an opportunity to exercise my skill.
But it looked as if I should not.