US-P09.001ab ।US-P09.001cd ॥
In plain words
Two things are to be recognized: subtlety, and how far a thing reaches. Track them through what can be known, each step beyond the last — beginning at smell, ending at the innermost Self — by letting go of every earlier one.
Close to the Sanskrit
Subtlety and pervasiveness are the two to be known, each successive one further along, beginning from smell, in [the knowables] that end in the inward-turned Self, through the abandoning of each preceding one.