Question

How do writers in the 18th century use satire?

Answer 1

With three primary scenarios, detailed below.

Explanation:

THE OBSERVER AND THE OBSERVED

These texts depend in large part on the vantage point from which the object of ridicule is seen. There are interesting thematic and generic differences between works in which the only observer is the reader and those in which characters function as observers also: thematically, reader-only satire relies heavily on perspective shifts for its humor, while interior-observer texts expand the ethical range of humor, encompassing the shame of the observed; generically, in dramatic works, observer characters embody the perspectives found in the narration of the reader-only texts.

A Bold Stroke for a Wife (Centlivre 1718)
Gulliver's Travels (Swift 1727)

THE REGULATION OF DESIRE

The self-described of these satires is to regulate and restrain unruly desire. Male desire is characterized as a single-minded passion, springing to an unusual degree from external promptings, and suffering inevitable disappointment. To regulate it, satire dilutes the ideal with morose reality. More frighteningly, female desire suffers from the problems of diffusion and mutability - it is too multifaceted to be controlled through its objects, and instead women themselves must be ridiculed.

Examples
The Rape of the Lock (Pope 1714)
Strephon and Chloe (Swift 1731)
The Lady's Dressing Room (Swift 1732)

SATIRE AS A FRAGILE MODE

Ideally, authors must delicately balance their works, avoiding inadvertent slippage into allegory, constraining the desire to indulge in bitter ranting, and finally ensuring an accurate interpretation by a potentially gullible reader. However, these texts are built specifically on these fault-lines, paradoxically using the inherent modal overlaps to sharpen their satire.

Examples
Tale of a Tub (Swift 1704)
Dunciad Variorum (Pope 1728-43)
A Modest Proposal (Swift 1729)

http://english.columbia.edu/18th-century-satire
See also:
http://www.inquiriesjournal.com/articles/545/satire-in-18th-century-british-society-alexander-popes-the-rape-of-the-lock-and-jonathan-swifts-a-modest-proposal