Dear all,
Here is a digital copy of Barnaud's Commentariolum ( and not Commentarium ) as stated wrongly in Husson's book on alchemical transmutations.
On the contrary the relevant pages seem to be correctly described: vide pages 10-13.
http://alfama.sim.ucm.es/dioscorides/consulta_libro.asp?ref=x533923114
Yours,
Jean