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.
Millard Fillmore was the first President to have a bathtub with running water. He was also the first President to have a stove in the White House.  This is false. The columni â¦ st H.L. Mencken, as a joke, said that Millard Fillmore installed the first bathtub in the White House.