Visible crew/equipment: In the widescreen version, when Alexander stops his time machine in the year 2030, he lowers the steps to get off. As he's doing this you can see the reflection of a few crew members in the pressure gauge located by the steps. (00:28:00 - 00:28:55)
Visible crew/equipment: When Alexander hears the child scream a foreign language and hears others, he looks down. As the others are climbing up the ropes and ladders, a safety strap "KEEPER" is seen holding one of the platforms up.
Answer: He's referring to the sound that the Morlocks' machinery makes from underground.
raywest ★