Top hat ribs and springs. His patent was described as: Some sources have taken this to describe an early folding top hat, although it is not explicitly stated whether Dollman's design was specifically for male or female headgear. Dollman's patent expired in 1825. In France, around 1840, Antoine Gibus's design for a spring-loaded collapsible top-hat proved so popular that hats made to it became known as "gibus". They were also often called "opera hats" due to the common practice of storing them in their flattened state under one's seat at the opera, though the term can also refer to any tall formal
Top Hat (company) recognized by numerous awards including Canadian Innovation Exchange Top 20 Program, "Best Canadian Startup of the Year" at the TechVibes Canadian Startup Awards, and Pauli Award for Company of the Year. Educators are able to adopt, customize and sell digital textbooks and course materials on the Top Hat Marketplace. Teachers can also collaborate with one another to create and update teaching material. Currently, 90 percent of course materials in the Marketplace are free. Top Hat Test allows educators to create and administer tests and assessments. Top Hat (company) Top Hat is a Canadian educational software company with its headquarters in