No sooner had the nature of India-rubber began to be developed, than the spirit of American enterprize commenced to work, in experimenting upon the various uses to which it is susceptible. Of course, the progress was at first slow and tedious. Charles Mackintosh, of England, seems to be the first individual who discovered the process of dissolving the gum in spirits of turpentine, and to introduce the manufacture of those goods which now bear his name. But it seems that as early as 1813, eight years prior to Mackintosh’s discovery, Jacob H. Hummel, of Philadelphia, had secured a patent for “India-rubber varnish.” What the method of preparation was, the “report” does not state. From that date to 1831, the spirit of investigation and experiment in this direction, lay dormant. The next step in this country, (in 1831,) was a patent secured for “_India-rubber Fluid_,” to render articles water-proof. In about one year from the issuing of this patent, Wait Webster, of New York, secured a patent for attaching India-rubber soles to boots and shoes. With the introduction of Chaffee’s patent for India-rubber shoes, in 1832, the spirit of invention, experiment and competition commenced, and has continued until the present time. The new, curious, and almost universal application of India-rubber and gutta-percha, in the industrial arts, has wrought a wonderful change, and has given an added stimulus to our manufacturing and commercial interests. The importance of these gums can hardly be over-estimated, and, it is hardly too much to predict that discoveries in the combination of gutta-percha and India-rubber with other substances, will yet be made, which will almost or wholly supersede the common sole-leather, now so extensively used. Already have patents been secured for _artificial leather_, that in appearance is hardly distinguishable from the best sole-leather. Its DURABILITY, it is contested, together with its CHEAPNESS, will, when the processes of its manufacture are perfected, give it a decided superiority over all other leather.