The special metaphor or conceit of each play attracts appropriate words and images, and creates a distinct atmosphere of its own. In the 'Knights' the air fairly reeks with the smell of leather and the tanyard. The 'Birds' transport us to a world of trillings and pipings, and beaks and feathers. There is a buzzing and a humming and a stinging throughout the 'Wasps.' The 'Clouds' drip with mist, and are dim with aërial vaporous effects. Aristophanes was the original inventor of Bob Acres's style of oath--the so-called referential or sentimental swearing. Dicæopolis invokes Ecbatana when Shamartabas struts upon the stage. Socrates in the 'Clouds' swears by the everlasting vapors. King Hoopoe's favorite oath is "Odds nets and birdlime." And the vein of humor that lies in over-ingenious, elaborate, and sustained metaphor was first worked in these comedies. All these excellences are summed up in the incomparable wealth and flexibility of his vocabulary. He has a Shakespearean mastery of the technicalities of every art and mystery, an appalling command of billingsgate and of the language of the cuisine, and would tire Falstaff and Prince Hal with base comparisons. And not content with the existing resources of the Greek vocabulary, he coins grotesque or beautiful compounds,--exquisite epithets like "Botruodöré" (bestower of the vine), "heliomanes" (drunk-with-sunlight), "myriad-flagoned phrases," untranslatable "port-manteaus" like "plouthugieia" (health-and-wealthfulness), and Gargantuan agglomerations of syllables like the portentous _olla podrida_ at the end of the 'Ecclesiazusæ.'