Complex sentence: Observations are reduced to color, odor, texture; memories are reduced to impressions, and "with the passage and dissolution of impression... (there is a) continual vanishing away, that strange, perpetual, weaving and unweaving of ourselves".
Split into simpler sentences: Observations are reduced to color, odor, texture; memories are reduced to impressions. "With the passage and dissolution of impression... (there is a) continual vanishing away, that strange, perpetual, weaving and unweaving of ourselves".