Montreal Protocol (1973) and the international agreement signed (1985 & 1987). The treaty is structured around several groups of halogenated hydrocarbons that deplete stratospheric ozone. All of the ozone depleting substances controlled by the Montreal Protocol contain either chlorine or bromine (substances containing only fluorine do not harm the ozone layer). Some ozone-depleting substances (ODSs) are not yet controlled by the Montreal Protocol, including nitrous oxide (N2O) For a table of ozone-depleting substances controlled by the Montreal Protocol see: For each group of ODSs, the treaty provides a timetable on which the production of those substances must be shot out and eventually
The Horse that Lost its Liberty (1484) under the title “Of the hors, of the hunter and of the hert” as teaching the moral given by Aristotle that "None ought to put hym self in subiection for to auenge hym on other". Samuel Croxall cites Horace’s conclusion that one should never yield one’s liberty to another for reasons of avarice. The fable was told as “The horse seeking vengeance on the stag ("Le cheval s'étant voulu venger du cerf") in La Fontaine's Fables and ends on the reflection that without personal liberty all other purchases are valueless: The alternative version of the fable concerns a boar