Final answer:
The excerpts are examples of how authors use figurative language and sensory imagery to activate the reader's senses and convey intricate emotions and settings in literature.
Step-by-step explanation:
The excerpts provided deal with descriptive figurative language and sensory imagery used to convey perceptions of the external world through taste, smell, and appearance. Employing literary techniques, authors can express complex ideas, emotions, and moods. For instance, describing something as having 'a sickly, oily smell, as of Chinese rice spirit' or being 'like nitric acid' invokes strong sensory reactions and potentially powerful emotions from the reader. Similarly, comparisons such as 'odorous like autumn's decaying leaves' help to establish atmosphere and context within a narrative. The use of descriptive language in literature serves to paint vivid images in the mind of the reader and engage their senses, often going beyond mere literal descriptions to explore deeper themes and sentiments.