Laughing Gas (1914 film) squabbling. The dentist arrives, and his first patient goes in, obviously in pain. The dentist prepares the nitrous oxide anaesthesic (also known commonly as "laughing gas" due to its effects prior to and after unconsciousness). With the man unconscious he pulls his tooth, but then he can't get him to wake up. He calls for Charlie and when he arrives the dentist runs off. Charlie tries to wake him and eventually tries hitting his head with a mallet. The man revives but starts laughing. Charlie knocks him out with the mallet. The dentist then returns and Charlie is sent to
Chemical formula as Cs[BH]. Parentheses ( ) can be nested inside brackets to indicate a repeating unit, as in [Co(NH)]Cl. Here, (NH) indicates that the ion contains six NH groups bonded to cobalt, and [ ] encloses the entire formula of the ion with charge +3. This is strictly optional; a chemical formula is valid with or without ionization information, and Hexamminecobalt(III) chloride may be written as [Co(NH)]Cl or [Co(NH)]Cl. Brackets, like parentheses, behave in chemistry as they do in mathematics, grouping terms together they are not specifically employed only for ionization states. In the latter case here, the parentheses indicate 6