So, for a tune, Roland and Margaret withdrew in a great measure their thoughts from the vicinity of the pole, and devoted themselves to their work at home.
When Roland Clewe had penetrated with his Artesian ray as deeply into the earth beneath him as the photic power of his instrument would admit, he had applied all the available force of his establishment--the men working in relays day and night--to the manufacture of the instruments which should give increased power to the penetrating light, which he hoped would make visible to him the interior structure of the earth, up to this time as unknown to man as had been the regions of the poles.
Roland had devoted a great deal of time to the arrangement of a system of reflectors, by which he hoped to make it possible to look down into the cylinder of light produced by the Artesian ray without projecting any portion of the body of the observer into the ray.

This had been done principally to provide against the possibility of a shock to Margaret, such as he received when he beheld a man with the upper part of his body totally invisible, and a section of the other portion laid bare to the eye of a person standing in front of it.

But his success had not been satisfactory.

It was quite different to look directly down into that magical perforation at his feet, instead of studying the reflection of the same, indistinctly and uncertainly revealed by a system of mirrors.
Consequently the plan of reflectors was discarded, and Roland determined that the right thing to do was to take Margaret into his confidence and explain to her why he and she should not stand together and look down the course of the Artesian ray.

She scolded him for not telling her all this before, and a permanent screen was erected around the spot on which the ray was intended to work, formed of Venetian blinds with fixed slats, so that the person inside could readily talk and consult with others outside without being seen by them.
As might well be supposed, this work with the "photic borer," as Clewe now called his instrument, was of absorbing interest.