"Yes. From the spectral shift and other factors. I'll have to get some other apparatus." He ran up to the laboratory, across the level field that lay black beneath the stars. He came back, panting, with spectrometer, terrestrial globe, and other articles.
"The tide is higher!" he cried as he looked through the blue-rimmed circle at the girl on the rock. "She'll be swept off before long!"
He mounted the spectrometer and fell to work with a will, taking observations through the telescope, adjusting prisms and diffraction gratings, reading electrometers and other apparatus, and stopping to make intricate calculations.
I helped him when I could, or stared through the ring of shining blue mist, where I could see the waves breaking higher about the exhausted girl who clung to the rock. Clouds of wind-whipped spray often hid her from sight. I knew that she would not have the strength to hold on much longer against the force of the rising sea.
Although driven almost to distraction by the horror of her predicament, he worked with a cool, swift efficiency. Only the pale, anxiety-drawn expression on his face showed how great was the strain. He finished the last spectrometer observation, snatched out a pad and fell to figuring furiously.
"Something queer here," he said presently, frowning. "A shift of the spectrum that I can't explain by distortion through three-dimensional space alone. I don't understand it."
We stared at the chilled and trembling girl on the rock.
"I'm almost afraid to try it. What if something went wrong?"
He turned to the terrestrial globe he had brought down and traced a line over it. He made a quick calculation on his pad, then made a fine dot on the globe with the pencil point.
"Here she is. On a rock some miles off Point Eugenia, on the coast of the Mexican State of Lower California. Most lonely spot in the world. No chance for a rescue. We must—