Maxwell looked at his watch.
“Perhaps I’d better. Benson wants to get back, anyway. Will you two go along?”—to Sprague and Starbuck.
“I don’t mind,” said the expert, with a barely perceptible nod to Starbuck; and after he had rearranged the chemicals on his newly made shelves the four left the office and had themselves dropped to the ground floor of the building.
It was while they were walking two and two down the street that Sprague dropped a few steps behind with Starbuck and passed him a carefully wrapped package which he took from under his coat.
“I have another little experiment in mind, Mr. Starbuck,” he said in low tones. “When we are on our way through the tunnel, watch your opportunity to drop out of the procession long enough to empty the contents of that package into the patent grease, which you will find, not floating on the oil, but in some sort of a receptacle let into the top of the oil-tank of that safety contrivance which Mr. Benson has so accurately described for us. I’m curious enough to want to prove up on my analysis of a few minutes ago—to see if it was correct.”
“What will happen if it was correct?”
“Nothing; nothing alarming, I assure you. But be careful not to get any of the stuff in that package on your hands when you break the paraffin seals. And perhaps it might be as well if you don’t let our young electrical friend see you do it. He might think we were messing in where we had no business to.”
Starbuck made a sign of complete understanding, and a few minutes later, when they reached the main street, made a time-saving suggestion.
“Suppose you folks take a taxi to the roundhouse,” he said. “I’ll mosey up to the despatcher’s office and get your clear-track orders for you.”
Maxwell approved the suggestion and they separated, Starbuck catching a passing electric car for the plaza-fronting railroad head-quarters, and Maxwell impressing the first auto hack he could find to take the remaining three of them directly to the western yards. The hackman drove across the city and let them out at the nearest street-crossing, and from thence they walked the final hundred yards over the ties of the shop track.