International Day for the Preservation of the Ozone Layer of the hole in the ozone layer was observed 30 years after the protocol was signed. Due to the nature of the gases responsible for ozone depletion their chemical effects are expected to continue for between 50 to 100 years. International Day for the Preservation of the Ozone Layer September 16 was designated by the United Nations General Assembly as the International Day for the Preservation of the Ozone Layer. This designation had been made on December 19, 2000, in commemoration of the date, in 1987, on which nations signed the Montreal Protocol on Substances that Deplete the Ozone Layer.
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