When did Snape invent his curses?

[jlnbtr]

No: HPFGUIDX 133332

--- In HPforGrownups at yahoogroups.com, "lapland874" <lapland874 at y...> 
wrote:
> Snape had apparently invented several curses as evidenced by the 
potion 
> book which Harry used all year.  However one curse was actually used 
> the previous year.  When James turned Snape upside down was on the 
day 
> of his OWL's exam.  The advanced potions book was not used by Snape 
> until the following year.  Unless he was already using it?  So did 
> Snape invent that curse/jinx or did he just figure it out and then 
> write it in the book?  Obviously some of them where truely his, but 
> maybe not all of them.
> 
> 
> Lapland874

Juli: He could have invented them long before his 6th year, but only 
during his 6th year he wrote them on his Advances Potions Book; or 
since he seems like a natural potion-maker, he could have been 
studying on his own, just like HArry has studied DADA all by himself 
(and Ron and HErmione, of course)

Juli