The virtuoso, Sir Nicholas Gimcrack, in Thomas Shadwell's 1676 play of the same name, is an avid student of vermin, spending huge sums on microscopes to examine them and too obsessed with his philosophical investigations to notice that his wife is unfaithful to him. He is learning to swim by imitating frogs, although he does not himself want to swim; imitating motions on land is enough. In a pivotal scene he is discovered lying on a table, attached to a swimming frog in a tank by a thread between his teeth, copying the frog's movements, his style judged by a swimming master.

Gimcrack describes blood transfusions between breeds of dog and between sheep and man, claiming in the first case that this exchanged the breeds, in the second that the human became sheep-like (though others suggest the experiments were all fatal). He is gullible and pays huge sums for eggs in which hairs have miraculously appeared (not noticing the needle holes in the shells). He keeps barrels of air collected from different locations, which he releases into his room, claiming that this is more refreshing than walking in the real places. He has pneumatic engines to create vacuums with which he investigates luminescence in glow-worms and rotting meat, while with his telescopes he claims to see architecture, animals and battles on the moon. […]