"Here—take the three machines I point to and set them on the table. That tall one with the two glass lenses in front—then the box with the vacuum tubes and sounding-board—and now the one with the metal disc on top. Now for the cylinder with the label ‘B-67’ pasted on it. Just stand in that Windsor chair to reach the shelf. Heavy? Never mind! Be sure of the number—B-67. Don’t bother that fresh, shiny cylinder joined to the two testing instruments—the one with my name on it. Set B-67 on the table near where you’ve put the machines—and see that the dial switch on all three machines is jammed over to the extreme left.