"And until such examination is made general, I should change the form of the signal lamps," remarked Dr. Macpherson. "Let the safety signal be of one uniform shape, and small; let the red, or danger signal, be of as different a shape as can be made, and large; so different that it could never fail to catch the eye. For, look you, a head deficient in the organ of colour will usually have that of form very much developed: and if a driver could not see the light, he might the form: and so save his train." "Quite right," said. Oliver. "In many of the railway calamities we read of, you find that a difference of testimony exists as to the colour of the signal exhibited. One side or the other is supposed to swear falsely; just as it has been in this case. But for the testimony of Colonel West, the jury would have returned a verdict against Cooper at once, and convicted him of falsehood. But rely upon it, the cause, generally speaking, of these conflicting and painful cases lies not in false swearing, but in colour-blindness." So concluded the professor. And so was concluded the long-adjourned puzzle that had set Coombe Dalton together by the ears. Once more the inquest was called for the last time; and the jury returned a verdict of "Accidental death." In the face of the proved defect in Cooper's capacity for distinguishing the different signals, how could they with justice punish him? He was sent forth, a free man so far, but discharged from his employment to begin the world again. Now, my friendly readers, the above is a bit of honest truth; a fact from the past. It may be that you will not believe it; may feel inclined to cavil at it. But search cases out and mark for yourselves. Blindness to colour is a far more common defect than the world suspects: it has existed--and does exist--in some of the railway-engine guards and drivers. CHAPTER X. Mary Jupp's Explosion. A frosty day in December. Time had gone on, winter had come in: the seasons go their round, whatever the world may be doing. How grew Clara Lake? Better? Well, she did not seem to grow much better; at any rate, she was not well, and the old doctor at Katterley, who had known her constitution from infancy, appeared puzzled. She dressed, as in her days of health, and went about the house: on fine days would go out for a walk in the sunshine: but she remained weak and debilitated, and could not get rid of her cough.