On this subject M. Michel Chevalier repeats what he heard from an eminent man who was Minister of Finance at the time when Daguerre received the national recompense which had been awarded him with the acclamations of all France. One of the Government clerks brought to this eminent personage proof that he too had made the same invention; and also there were the labours of M. Niepce de Saint Victor, analogous to those of M. Daguerre. [M. Passy, the chairman of the meeting, confirmed the statement of M. Michel Chevalier on this fact.] M. Michel Chevalier, in continuation, remarked that in our time industrial arts are subject to great changes in the details of their operations. Independently of the general alterations which from time to time completely change the face of any given manufacture, there is no important workshop where some useful notion is not occasionally suggested by some mechanic or overseer, which leads to minor improvements [_un perfectionnement de détail_]. It would be an abuse to grant, during a term of fifteen years, or even a much shorter, exclusive use of any particular improvements to any single individual. It would not be just, for it is quite possible that the idea might have occurred to another at the same time, or that it might occur the next day. It would even be against the general interest, for it would fetter competition, which is the chief motor in the progress of the useful arts. But it is said inventors are useful to society; we must therefore recompense them. To this M. Michel Chevalier answers that it may be too liberal to confer the flattering title of inventor on men who, when a veritable discovery has been made by _savants_, push themselves forward to appropriate the profits, in securing by Patents the various special applications which may be made of it. Besides, there are different sorts of recompenses; there are other than material rewards, and these are not the least coveted. The _savants_ who are the greatest discoverers are satisfied with these immaterial rewards—honour, glory, and reputation. The example is worthy of recommendation; not but it is quite allowable for a man to extract from his labour [_travaux_] whatever material recompense he can. But, in many cases at least, the Patent is not necessary for this purpose. The authors of some useful discovery would often have the resource of keeping their secret and working the invention themselves. That would last for a time. Even under the system of Patents several inventors have thus sought and found an adequate remuneration. Thus the famous Prussian steel manufacturer, M. Krupp, has taken out no Patent, and yet has made a colossal fortune; also M. Guimet, of Lyons, inventor of French blue. Their secret remained in their own hands for more than fifteen years, the maximum duration that their Patent would have had in France.