Suffix [edit]. -en. 1  Suffix for definite form singular of many common gender nouns, in particular those which end in a consonant or a stressed-i; see also-n. 2  Suffix for definite form plural of neuter nouns ending with consonant.
Events Leading up to Heliograph When NiÃ©pce first began working with his son who would draw the images they used in lithography because NiÃ©pce could not draw well. During that time the camera obscura was only used as a guide for drawing. This collaboration stopped when his son was drafted into the army and went to fight in the Battle of Waterloo.
Rubidium is pronounced as roo-BID-ee-em. History and Uses: Rubidium was discovered by the German chemists Robert Bunsen and Gustav Kirchhoff in 1861 while analyzing samples of the mineral lepidolite (KLi 2 Al(Al, Si) 3 O 10 (F, OH) 2) with a device called a spectroscope. The sample produced a set of deep red spectral lines they had never seen before.