For example, for the Gases under pressure hazard class, the hazard categories are Compressed gas, Liquefied gas, Refrigerated liquefied gas and Dissolved gas. These classes relate to the physical state of the gas when packaged and do not describe the degree of hazard.
1 In 1596, a flush toilet was invented and built for Queen Elizabeth I by her Godson, Sir John Harrington. 2  The first patent for the flushing toilet was issued to Alexander Cummings in 1775. 3  During the 1800s, people realized that poor sanitary conditions caused diseases.
In 1596 A.D. Sir John Harrington, godson of Queen Elizabeth, made the first flush toilet. John made it mainly for himself and the Queen.Unfortunately, his friends made fun of him and he never made another one until two hundred years later alexander Cumming reinvented it! He called it the now known water closet.n 1596 A.D. Sir John Harrington, godson of Queen Elizabeth, made the first flush toilet. John made it mainly for himself and the Queen. Unfortunately, his friends made fun of him and he never made another one until two hundred years later alexander Cumming reinvented it!