Jellicle cats Jellicle cats "Jellicle cats", or simply the "Jellicles", are a type of feline mentioned in T. S. Eliot's book "Old Possum's Book of Practical Cats", and in "Cats", a stage musical written by Andrew Lloyd Webber and based on the book. Introduced in Eliot's poem "The Song of the Jellicles", they were originally depicted as commonly nocturnal gray, scruffy cats. Specifically, Eliot mentions that they like to gather at an event called the "Jellicle Ball". In the musical, a sub-plot surrounds the disappearance of the Jellicle patriarch Old Deuteronomy. The names are taken from Eliot's poem "The Naming of Cats"
What Engineers Know and How They Know It What Engineers Know and How They Know It What Engineers Know and How they Know It: Analytical Studies from Aeronautical History (The Johns Hopkins University Press, 1990) () is a historical reflection on engineering practice in US aeronautics from 1908 to 1953 written by an accomplished practitioner and instructor. This period represents the dawn of aviation which was fraught with uncertainties and numerous paths to many possible worlds. The book captures two main conclusions from this period. The first order conclusion of this book is about "what engineers know." Five case studies from the history of aeronautical engineering are used