Matter (Divisibility Of). It is scarcely credible, yet a slip of ivory, of an inch in length, may be divided into a hundred equal parts, each of which is distinctly visible, but by the application of a very fine screw, 5,000 equi-distant lines, in the space of a quarter of an inch, can be traced on a surface of steel, or glass, with the one point of a diamond, producing delicate and varied colours, thereby proving that the beautiful hues of mother-of-pearl, peacock pearl, and the less delicate appearance of what are termed watered fabrics, are the effect of irregularity of surface, not, as might be sup-posed in the case of mother-of-pearl and peacock pearl, the result of variety of substance. A single pound of cotton has been spun into a thread seventy-six miles in length, and the same quantity of wool has been extended into a thread of ninety-fire miles, the diameters of those threads being only the 350th and 400th parts of an inch.