The first thing noticed was that the window was open; and annoyed that the mist of a damp morning should be admitted, I hurriedly closed it, thinking then no more of the matter. It wanted quite an hour to the time appointed, and the interval was employed in superintending the alteration of a few bolts and nuts, which Mr Girtley wanted tightened, and as I watched the great engineer, a man whose name was now an authority throughout Europe, and who was constantly refusing contracts, pull off his coat, take a spanner, and help his men, I began to realise that it was his personal attention to small matters and his watchful supervision that had raised him to his present position. "Nice hands!" he said, laughing, as he held them out all over blacklead and oil. "Wise lad, you were, Tom, to leave it, and take to your parchment and pounce." There was a covert sneer in his words, which Tom seemed to take, for he said quickly: "Perhaps, father, I may help you as much with my brain as I used to help you with my hands." "Yes, yes, of course, my boy, and we must have lawyers. Well, Grace, how do you feel about it now?" "I think I'd ease that nut a little, sir," I said, pointing to one part of the machine. "Why?" he said sharply. "I fancy that there will be so much stress upon that wheel that it will be better to give it as much freedom as we can, and, perhaps I am wrong, sir, but it strikes me--" I glanced at Hallett, and felt the blood flush to my face, for I felt that what I was about to say must sound very cruel to him. "Go on, Antony," he said kindly; but I saw that he was very pale. "It strikes you?" said Mr Girtley. "That this is the weak part of the contrivance. Here falls the stress; and, when it is running at full speed, I feel sure that the slight structure of this portion will tell against the machine doing good work, and it may result in its breaking down." "Go on," said Mr Girtley bluntly; for I had stopped, feeling uncomfortable at the dead silence that had fallen upon the group. "It is not a question of efficiency," I said, "but one of detail, of substantiality and durability. At first sight it seems as if it would make the machine cumbersome, but I feel sure that if we made that shaft and its wheel four times the thickness--that is to say, excessively massive, we should get a firm, solid regularity in the working, a fourth of the vibration, and be able to dispense with this awkward fly-wheel. My dear Hallett," I exclaimed hurriedly, as I saw how his pallor had increased, "pray forgive me. I was quite led away by my thoughts. These are but suggestions. I daresay I was wrong." "Wrong!" exclaimed Mr Girtley, catching my hand in his, and giving it a grip that made me wince. "Every word you have said, my boy, is worth gold. Tom, I'd have given ten thousand pounds to have heard you speak like that."