“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.”
“But then, you see, I could not, father,” said his son good-humouredly. “Antony Grace here is a born engineer, and you’ll have to make him a partner one of these days.”
I hardly heard their words, for my anxiety about Hallett. I seemed to have been trampling upon his hopes, and as if I had been wanting in forethought after having the superintendence of the manufacture for so long.
“I ought to have suggested these alterations before,” I faltered.
“How could you?” said Mr Girtley gruffly. “You only saw the failing just now. I can see it, of course, when you point it out. We only climb by our falls, Grace. Locomotives were only got to their present perfection after no end of failures. Well, Mr Hallett, what do you say?”