SSC Junior Engineer Notification. SSC Junior Engineer 2015 Notification:-. Date of Notification:- 11-07-2015. Last Date of Receiving Application:- Part-I 07-08-2015 (upto 5:00 P.M.) Part-II 10-08-2015 (upto 5:00 P.M.). SSC Junior Engineer Exam 2015 Date:- 20-12-2015.
Incandescent Gas Lantern Mantles General The thorium-containing incandescent mantle was invented in 1884 by Carl Auer von Welsbach, an Austrian chemist, and it is sometimes referred to as a Welsbach mantle or Auerlicht.This invention resulted in the first commercial use of the element thorium.he thorium-containing incandescent mantle was invented in 1884 by Carl Auer von Welsbach, an Austrian chemist, and it is sometimes referred to as a Welsbach mantle or Auerlicht. This invention resulted in the first commercial use of the element thorium.
Leonardo da Vinci at the beginning of the 16th century was credited with inventing the first hygrometer that used a ball of wool to provide this indication of humidity level. First Mechanical Air Cooler. Da Vinci was likely the first to use a mechanical air cooler. This air cooler consisted of a hollow water wheel with an air passage constructed to guide the air from the water wheel to his patron's wife's boudoir. The air was cooled by the splashing and evaporation of water during operation of the water wheel.