“For who indeed can paint like nature?” Robert John Thornton lamented in 1798, admiring the vivid hues of the roses and tulips in England’s royal gardens. The British physician was just beginning the eight-year-long process of publishing The Temple of Flora, one of the most lavishly produced botanical works in history. This month Taschen releases a new edition of his 28 oversized color plates, which are as captivating to the student of nature as to the connoisseur of 18th-century still-life painting.

Although Thornton’s original book was unquestionably sui generis, extravagance was a characteristic of his era. Twenty years before Thornton began The Temple of Flora, Georges-Louis Leclerc, comte de Buffon, published the final installment of what was arguably the most ambitious opus of the Enlightenment: his 44-volume Histoire naturelle, générale et particulière. Featuring thousands of hand-colored engravings, this epic encyclopedia of the natural world set the scientific standard for its age in a form sumptuous enough to enrapture even Catherine the Great, who insisted on being sent a copy—for which she never paid.

Buffon did not intend for the publication of Histoire naturelle to span nearly three decades. On the contrary, the work began as a minor administrative task. Appointed at the age of 31 as superintendent of the Jardin du Roi, he agreed to catalogue the specimens in the prestigious scientific institution’s natural-history cabinet. If the cabinet was similar to many royal collections around the world, its cataloguer was unlike most superintendents. He was a mathematical genius with an interest in subjects ranging from tree growth to rocket flight. For all his mathematical acumen, Buffon’s calculations were less than precise, or consistent, sometimes leading him to believe that the earth had been around for 75,000 years, other times bringing him to the conclusion that the planet was a million years old. In contrast, his descriptions of bird species were the epitome of scientific accuracy and would be a standard reference for more than a century. Next month, Rizzoli will publish All the World’s Birds, an impressive selection from the volumes of Histoire naturelle that were devoted to ornithology.

Although Buffon’s language was often evocative—particularly with respect to birdsong, as when attributing “smooth volubility” to the nightingale’s call—he also understood the limitations of words and the superiority of pictures in communicating color. And so, in the interest of science, he made his writing secondary to the illustrations. Precisely drawn and engraved by the French artist François Nicolas Martinet, the 973 plates are the reason the book was admired by ornithologists and royalty alike. The pairing of lush plumage with sparse backgrounds, intended to promote scientific clarity, also made mesmerizing art of the birds’ magnificence.

Thornton was no less interested in accurate depiction in his Temple of Flora, but he was equally driven by the desire to deify 18th-century science, and the resulting work is as muddled as Buffon’s is straightforward. Some of England’s most talented artists, such as the portraitist Philip Reinagle, were engaged to paint the subjects Thornton selected, ranging from familiar tulips to the exotic maggot-bearing stapelia. To reproduce their paintings, Thornton employed the finest engravers of the era, who used practically every known printing technique, including mezzotint and aquatint, to capture the full range of color.

Yet no one could paint, or print, like nature. Nobody could satisfy Thornton in this, or in his desire to set the plants in dramatic landscapes—decked with temples and clock towers and populated by sparrows and cupids—that were more suitable as backdrops for a romantic opera than for a scientific study. Paintings were remade, plates reengraved as Thornton’s inheritance trickled away. He secured illustrations for fewer than half the 70 exotic plants he intended to document before he was forced to sell everything in a lottery, falling back on the practice of medicine.