Nouveau procédé de tannage du cuir
… la demande du pétitionnaire n’est pas digne d’un accueil favorable, par les motifs, que les moyens proposés par lui sont déjà connus depuis 1843, où l'on en trouve la description dans le “London Journal of arts and sciences”, volume 22 de 1843.
 This was not the only change in the patent granting procedure. The communication channels between the Luxembourg and the Dutch authorities had also been changed; in the “Valerius” case, however, they had not been respected. Dr Simons was involved in the matter which resulted in a rather nasty exchange of letters between Luxembourg and La Haye and prompted the Luxembourg authorities to decide to no longer have patent examinations conducted in La Haye but by the Chambre de Commerce in Luxembourg.
 « This invention consists in a novel mode of conducting the process of tanning, and in the employment of certain mixtures or compositions, in place of the ordinary tanning liquid, by which means a very considerable economy in time, labour, and cost of material is effected. …The skins and hides, after having undergone the operations of washing, removing the hair, and swelling, are submitted to the action of such metallic, saline, and earthy substances, as may be decomposed by the skins and hides, or may combine with the same. Among these substances, the one that seems preferable is the bibasic sulphate of sesquioxide of iron, or the basic red sulphate of iron, or the sub-sulphate of peroxide of iron. »