The canary was much sought-after as a cage bird even in the Age of Enlightenment and is still a popular pet today. The comparatively unspectacular nightingale was kept as a cage bird for its song. Special manuals were published explaining how a songbird might be trained. This could be done with the aid of special bird flutes tuned to the same register as the birds. Before any major performance the feathered divas were specially coiffed with the aid of curling tongs.