Into this duct the ranks of cells around it pour out the peptic juice.
I heard a muffled clank; then a hum began, echoing up the duct.
I reached the top of the duct and pushed against the slot cover.
And there was that hazard here, for every duct looked like every other one.
The operator then carefully examines the duct preparatory to cutting it.
The penultimate section, ...