of the planets from the sun could not be preserved, nor their relative magnitudes; but what was of more importance, their relative velocities in their orbits were maintained.  The day came when the machine was to be first used.  Miriam insisted that there should be no experiments with it beforehand.  She desired, even at the risk of disappointment, to see a dramatic start into existence.  She did not wish her pleasure to be spoiled and her excitement to be diminished by trials.  Her husband humoured her, but secretly he took care that every preventible chance of a breakdown should be removed.  When she was absent, he tested every pinion and every cog, eased a wheel here and an axle there, and in truth what he had to do in this way with file and sandpaper was almost equal to the labour spent upon saw and chisel.  Infinite adjustment was necessary to make the idea a noiseless, smooth practical success, and infinite precautions had to be taken and devices invented which were not foreseen when the drawing first appeared on paper.  With some of these difficulties Miriam, of course, was acquainted.  They would not probably have been so great to a professional instrument-maker, but they were very considerable to an amateur.  Farrow selected the best-seasoned wood he could find, but it frequently happened that after it was cut it warped a little, and the slightest want of truth threw all the connected part out of gear.  Miriam learned something when she saw that a wheel whose revolution was not in a perfect plane could give rise to so much annoyance, and she learned something also when she saw how her husband, in the true spirit of a genuine craftsman, remained discontented if there was the slightest looseness in a bearing.

“Do you think it matters?” said she.

“Matters!  Don’t you see that if it goes on it gets worse?  Every wobble increases the next, and not only so, it sets the whole thing wobbling.”

“Couldn’t you manage to put a piece on?  Suppose you lined that hole with something.”

“Oh, no!  Not the slightest use; out it must come, and a new one must be put in.”

At length the day came for the start.  Farrow had made a trial by himself the night before, and nothing could be better.  Mr. Armstrong came over, and after tea they all three went upstairs into the large garret which had been used as a workshop.  The great handle was taken down and fitted into its place, Mr. Armstrong standing at one end and Miriam and her husband at the other.  Obedient to the impulse, every planet at once answered; Mercury with haste, and Saturn with such deliberation that scarcely any motion was perceptible.  The Earth spun its diurnal round, the Moon went forward in her monthly orbit.  The lighted ground-glass globe which did duty for the sun showed night and day and the seasons.  Miriam was transported, when suddenly there was a jerk and a stop.  Something was wrong, and Farrow, who was fortunately turning with great caution, gave a cry such as a man might utter who was suddenly struck a heavy blow.  He recovered himself instantly, and luckily at the very first glance saw what was the matter.  The nicety of his own handicraft was the cause of the disaster.  A shaving not much thicker than a piece of writing-paper had dropped between two cogs.  A gentle touch of a quarter of an inch backwards released it.