Among the various circumstances which influence the progress of physical science in this country, one of the most prominent is the _Patent_ law--a law in its intention beneficent; but whether the practical working of it be useful, either to science or its cultivators, is a matter of grave doubt. Of the greater number of patents enrolled in that depot of practical science, Chancery Lane, by far the majority are beneficial only to the revenue; and on the question of public economy, whether or not the price paid by miscalculating ingenuity is a fair and politic source of revenue, we shall not enter; but on the reasons which lead so many to be dupes of their own self-esteem, a few words may not be misspent. The chief reason why a vast number of patents are unsuccessful, is, that it takes a long time (longer generally than fourteen years, the statutable limit of patent grants) to make the workmen of a country familiar with a new manufacture. A party, therefore, who proposes patenting an invention, and who sits down and calculates the value of the material, the time necessary for its manufacture, and other essential data; comparing these with the price at which it can be sold to obtain a remunerative profit, seldom takes into consideration the time necessary, first, to accustom the journeymen workers to its construction, and secondly, to make known to the public its real value. In the present universal competition, puffing is carried on to such an extent, that, to give a fair chance of success, not only must the first expense of a patent be incurred--no inconsiderable one either, even supposing the patentee fortunate enough to escape litigation--but a large sum of money must be invested in advertisements, with little immediate return; hence it is that the most valuable patents, viewed in relation to their scientific importance, their ultimate public benefit, and the merits of their inventors, are seldom the most lucrative, while a patent inkstand, a boot-heel, a shaving case, or a button, become rapidly a source of no inconsiderable profit. Is this beneficial to inventors? Is it an encouragement of science, or a proper object of legislative provision, that the improver of the most trivial mechanical application should be carefully protected, while those who open the hidden sources of myriads of patents, are unrewarded, and incapable of remunerating themselves? We seriously incline to think that, as the matter at present stands, an entire erasure from the statute-books of patent provision would be of service to science, and perhaps to the community; each tradesman would depend for success upon his own activity, and the perfection he could give his manufacture, and the scientific searcher after experimental truths would not find his path barred by prohibitions from speculative empirics.