I agree it is intriguing that these tests showed the French howitzer firing to that angle, but not the licorne. Perhaps it was a test to destruction, and the licornes fell apart before reaching that angle?
I am sorry, I probably misled you. Scharnhorst gives no information on unicorns in the book I refer to. The book was printed in 1787, when Scharnhorst was a Hannoverian officer. The book contains information on Hannoverian, British, French, Danish, Prussian, and Saxon artillery. The data on ranges achieved at different elevation angles are taken from various sources, they are not obtained by Scharnhorst himself, probably except the data on Hannoverian artillery.